]> granicus.if.org Git - postgresql/commitdiff
Make use of plancache module for SPI plans. In particular, since plpgsql
authorTom Lane <tgl@sss.pgh.pa.us>
Thu, 15 Mar 2007 23:12:07 +0000 (23:12 +0000)
committerTom Lane <tgl@sss.pgh.pa.us>
Thu, 15 Mar 2007 23:12:07 +0000 (23:12 +0000)
uses SPI plans, this finally fixes the ancient gotcha that you can't
drop and recreate a temp table used by a plpgsql function.

Along the way, clean up SPI's API a little bit by declaring SPI plan
pointers as "SPIPlanPtr" instead of "void *".  This is cosmetic but
helps to forestall simple programming mistakes.  (I have changed some
but not all of the callers to match; there are still some "void *"'s
in contrib and the PL's.  This is intentional so that we can see if
anyone's compiler complains about it.)

16 files changed:
contrib/spi/refint.c
contrib/spi/timetravel.c
doc/src/sgml/spi.sgml
src/backend/executor/spi.c
src/backend/utils/adt/ri_triggers.c
src/backend/utils/adt/ruleutils.c
src/backend/utils/adt/xml.c
src/backend/utils/cache/plancache.c
src/include/executor/spi.h
src/include/executor/spi_priv.h
src/include/utils/plancache.h
src/pl/plpgsql/src/pl_exec.c
src/pl/plpgsql/src/plpgsql.h
src/test/regress/expected/plancache.out
src/test/regress/regress.c
src/test/regress/sql/plancache.sql

index c0c55eb080e07140cfa399f487b1ca9a0462f2c4..d88975d5e9cb6a6d5b586c365e89afc443164b45 100644 (file)
@@ -19,7 +19,7 @@ typedef struct
 {
        char       *ident;
        int                     nplans;
-       void      **splan;
+       SPIPlanPtr *splan;
 }      EPlan;
 
 static EPlan *FPlans = NULL;
@@ -163,7 +163,7 @@ check_primary_key(PG_FUNCTION_ARGS)
         */
        if (plan->nplans <= 0)
        {
-               void       *pplan;
+               SPIPlanPtr      pplan;
                char            sql[8192];
 
                /*
@@ -191,7 +191,7 @@ check_primary_key(PG_FUNCTION_ARGS)
                if (pplan == NULL)
                        /* internal error */
                        elog(ERROR, "check_primary_key: SPI_saveplan returned %d", SPI_result);
-               plan->splan = (void **) malloc(sizeof(void *));
+               plan->splan = (SPIPlanPtr *) malloc(sizeof(SPIPlanPtr));
                *(plan->splan) = pplan;
                plan->nplans = 1;
        }
@@ -413,11 +413,11 @@ check_foreign_key(PG_FUNCTION_ARGS)
         */
        if (plan->nplans <= 0)
        {
-               void       *pplan;
+               SPIPlanPtr      pplan;
                char            sql[8192];
                char      **args2 = args;
 
-               plan->splan = (void **) malloc(nrefs * sizeof(void *));
+               plan->splan = (SPIPlanPtr *) malloc(nrefs * sizeof(SPIPlanPtr));
 
                for (r = 0; r < nrefs; r++)
                {
index a1f69a10fbb7292ae2dce4b0d28baf01688a64ba..4b238fa425fbabbc57a6190594f0ded102810fda 100644 (file)
@@ -24,7 +24,7 @@ Datum         get_timetravel(PG_FUNCTION_ARGS);
 typedef struct
 {
        char       *ident;
-       void       *splan;
+       SPIPlanPtr      splan;
 }      EPlan;
 
 static EPlan *Plans = NULL;            /* for UPDATE/DELETE */
@@ -308,7 +308,7 @@ timetravel(PG_FUNCTION_ARGS)
        /* if there is no plan ... */
        if (plan->splan == NULL)
        {
-               void       *pplan;
+               SPIPlanPtr      pplan;
                Oid                *ctypes;
                char            sql[8192];
                char            separ = ' ';
index 90a68a5d01bb9046d26d123ee62c906d0ce56e11..c7c4304b3a7dd557565f2dcbf2afafb306616c5c 100644 (file)
@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/spi.sgml,v 1.53 2007/02/18 01:47:40 momjian Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/spi.sgml,v 1.54 2007/03/15 23:12:06 tgl Exp $ -->
 
 <chapter id="spi">
  <title>Server Programming Interface</title>
@@ -14,7 +14,7 @@
   <acronym>SQL</acronym> commands inside their functions.
   <acronym>SPI</acronym> is a set of
   interface functions to simplify access to the parser, planner,
-  optimizer, and executor. <acronym>SPI</acronym> also does some
+  and executor. <acronym>SPI</acronym> also does some
   memory management.
  </para>
 
@@ -322,7 +322,8 @@ SPI_execute("INSERT INTO foo SELECT * FROM bar", false, 5);
 
   <para>
    You can pass multiple commands in one string, but later commands cannot
-   depend on the creation of objects earlier in the string.
+   depend on the creation of objects earlier in the string, because the
+   whole string will be parsed and planned before execution begins.
    <function>SPI_execute</function> returns the
    result for the command executed last.  The <parameter>count</parameter>
    limit applies to each command separately, but it is not applied to
@@ -699,7 +700,7 @@ int SPI_exec(const char * <parameter>command</parameter>, long <parameter>count<
 
  <refsynopsisdiv>
 <synopsis>
-void * SPI_prepare(const char * <parameter>command</parameter>, int <parameter>nargs</parameter>, Oid * <parameter>argtypes</parameter>)
+SPIPlanPtr SPI_prepare(const char * <parameter>command</parameter>, int <parameter>nargs</parameter>, Oid * <parameter>argtypes</parameter>)
 </synopsis>
  </refsynopsisdiv>
 
@@ -790,6 +791,13 @@ void * SPI_prepare(const char * <parameter>command</parameter>, int <parameter>n
  <refsect1>
   <title>Notes</title>
 
+  <para>
+   <type>SPIPlanPtr</> is declared as a pointer to an opaque struct type in
+   <filename>spi.h</>.  It is unwise to try to access its contents
+   directly, as that makes your code much more likely to break in
+   future revisions of <productname>PostgreSQL</productname>.
+  </para>
+
   <para>
    There is a disadvantage to using parameters: since the planner does
    not know the values that will be supplied for the parameters, it
@@ -816,7 +824,7 @@ void * SPI_prepare(const char * <parameter>command</parameter>, int <parameter>n
 
  <refsynopsisdiv>
 <synopsis>
-int SPI_getargcount(void * <parameter>plan</parameter>)
+int SPI_getargcount(SPIPlanPtr <parameter>plan</parameter>)
 </synopsis>
  </refsynopsisdiv>
 
@@ -834,7 +842,7 @@ int SPI_getargcount(void * <parameter>plan</parameter>)
 
   <variablelist>
    <varlistentry>
-    <term><literal>void * <parameter>plan</parameter></literal></term>
+    <term><literal>SPIPlanPtr <parameter>plan</parameter></literal></term>
     <listitem>
      <para>
       execution plan (returned by <function>SPI_prepare</function>)
@@ -847,9 +855,10 @@ int SPI_getargcount(void * <parameter>plan</parameter>)
  <refsect1>
   <title>Return Value</title>
   <para>
-    The expected argument count for the <parameter>plan</parameter>, or
-    <symbol>SPI_ERROR_ARGUMENT</symbol> if the <parameter>plan
-    </parameter> is <symbol>NULL</symbol>
+    The count of expected arguments for the <parameter>plan</parameter>.
+    If the <parameter>plan</parameter> is <symbol>NULL</symbol> or invalid,
+    <varname>SPI_result</varname> is set to <symbol>SPI_ERROR_ARGUMENT</symbol>
+    and <literal>-1</literal> is returned.
   </para>
  </refsect1>
 </refentry>
@@ -871,7 +880,7 @@ int SPI_getargcount(void * <parameter>plan</parameter>)
 
  <refsynopsisdiv>
 <synopsis>
-Oid SPI_getargtypeid(void * <parameter>plan</parameter>, int <parameter>argIndex</parameter>)
+Oid SPI_getargtypeid(SPIPlanPtr <parameter>plan</parameter>, int <parameter>argIndex</parameter>)
 </synopsis>
  </refsynopsisdiv>
 
@@ -890,7 +899,7 @@ Oid SPI_getargtypeid(void * <parameter>plan</parameter>, int <parameter>argIndex
 
   <variablelist>
    <varlistentry>
-    <term><literal>void * <parameter>plan</parameter></literal></term>
+    <term><literal>SPIPlanPtr <parameter>plan</parameter></literal></term>
     <listitem>
      <para>
       execution plan (returned by <function>SPI_prepare</function>)
@@ -912,11 +921,13 @@ Oid SPI_getargtypeid(void * <parameter>plan</parameter>, int <parameter>argIndex
  <refsect1>
   <title>Return Value</title>
   <para>
-    The type id of the argument at the given index, or
-    <symbol>SPI_ERROR_ARGUMENT</symbol> if the <parameter>plan</parameter> is
-    <symbol>NULL</symbol> or <parameter>argIndex</parameter> is less than 0 or
+    The type id of the argument at the given index.
+    If the <parameter>plan</parameter> is <symbol>NULL</symbol> or invalid,
+    or <parameter>argIndex</parameter> is less than 0 or
     not less than the number of arguments declared for the
-    <parameter>plan</parameter>
+    <parameter>plan</parameter>,
+    <varname>SPI_result</varname> is set to <symbol>SPI_ERROR_ARGUMENT</symbol>
+    and <symbol>InvalidOid</symbol> is returned.
   </para>
  </refsect1>
 </refentry>
@@ -939,7 +950,7 @@ Oid SPI_getargtypeid(void * <parameter>plan</parameter>, int <parameter>argIndex
 
  <refsynopsisdiv>
 <synopsis>
-bool SPI_is_cursor_plan(void * <parameter>plan</parameter>)
+bool SPI_is_cursor_plan(SPIPlanPtr <parameter>plan</parameter>)
 </synopsis>
  </refsynopsisdiv>
 
@@ -964,7 +975,7 @@ bool SPI_is_cursor_plan(void * <parameter>plan</parameter>)
 
   <variablelist>
    <varlistentry>
-    <term><literal>void * <parameter>plan</parameter></literal></term>
+    <term><literal>SPIPlanPtr <parameter>plan</parameter></literal></term>
     <listitem>
      <para>
       execution plan (returned by <function>SPI_prepare</function>)
@@ -978,9 +989,10 @@ bool SPI_is_cursor_plan(void * <parameter>plan</parameter>)
   <title>Return Value</title>
   <para>
     <symbol>true</symbol> or <symbol>false</symbol> to indicate if the
-    <parameter>plan</parameter> can produce a cursor or not, or
-    <symbol>SPI_ERROR_ARGUMENT</symbol> if the <parameter>plan</parameter>
-    is <symbol>NULL</symbol>
+    <parameter>plan</parameter> can produce a cursor or not.
+    If the <parameter>plan</parameter> is <symbol>NULL</symbol> or invalid,
+    <varname>SPI_result</varname> is set to <symbol>SPI_ERROR_ARGUMENT</symbol>
+    and <symbol>false</symbol> is returned.
   </para>
  </refsect1>
 </refentry>
@@ -1001,7 +1013,7 @@ bool SPI_is_cursor_plan(void * <parameter>plan</parameter>)
 
  <refsynopsisdiv>
 <synopsis>
-int SPI_execute_plan(void * <parameter>plan</parameter>, Datum * <parameter>values</parameter>, const char * <parameter>nulls</parameter>,
+int SPI_execute_plan(SPIPlanPtr <parameter>plan</parameter>, Datum * <parameter>values</parameter>, const char * <parameter>nulls</parameter>,
                      bool <parameter>read_only</parameter>, long <parameter>count</parameter>)
 </synopsis>
  </refsynopsisdiv>
@@ -1022,7 +1034,7 @@ int SPI_execute_plan(void * <parameter>plan</parameter>, Datum * <parameter>valu
 
   <variablelist>
    <varlistentry>
-    <term><literal>void * <parameter>plan</parameter></literal></term>
+    <term><literal>SPIPlanPtr <parameter>plan</parameter></literal></term>
     <listitem>
      <para>
       execution plan (returned by <function>SPI_prepare</function>)
@@ -1091,8 +1103,8 @@ int SPI_execute_plan(void * <parameter>plan</parameter>, Datum * <parameter>valu
      <term><symbol>SPI_ERROR_ARGUMENT</symbol></term>
      <listitem>
       <para>
-       if <parameter>plan</parameter> is <symbol>NULL</symbol> or
-       <parameter>count</parameter> is less than 0
+       if <parameter>plan</parameter> is <symbol>NULL</symbol> or invalid,
+       or <parameter>count</parameter> is less than 0
       </para>
      </listitem>
     </varlistentry>
@@ -1143,7 +1155,7 @@ int SPI_execute_plan(void * <parameter>plan</parameter>, Datum * <parameter>valu
 
  <refsynopsisdiv>
 <synopsis>
-int SPI_execp(void * <parameter>plan</parameter>, Datum * <parameter>values</parameter>, const char * <parameter>nulls</parameter>, long <parameter>count</parameter>)
+int SPI_execp(SPIPlanPtr <parameter>plan</parameter>, Datum * <parameter>values</parameter>, const char * <parameter>nulls</parameter>, long <parameter>count</parameter>)
 </synopsis>
  </refsynopsisdiv>
 
@@ -1163,7 +1175,7 @@ int SPI_execp(void * <parameter>plan</parameter>, Datum * <parameter>values</par
 
   <variablelist>
    <varlistentry>
-    <term><literal>void * <parameter>plan</parameter></literal></term>
+    <term><literal>SPIPlanPtr <parameter>plan</parameter></literal></term>
     <listitem>
      <para>
       execution plan (returned by <function>SPI_prepare</function>)
@@ -1242,7 +1254,7 @@ int SPI_execp(void * <parameter>plan</parameter>, Datum * <parameter>values</par
 
  <refsynopsisdiv>
 <synopsis>
-Portal SPI_cursor_open(const char * <parameter>name</parameter>, void * <parameter>plan</parameter>,
+Portal SPI_cursor_open(const char * <parameter>name</parameter>, SPIPlanPtr <parameter>plan</parameter>,
                        Datum * <parameter>values</parameter>, const char * <parameter>nulls</parameter>,
                        bool <parameter>read_only</parameter>)
 </synopsis>
@@ -1268,6 +1280,11 @@ Portal SPI_cursor_open(const char * <parameter>name</parameter>, void * <paramet
    to the procedure's caller provides a way of returning a row set as
    result.
   </para>
+
+  <para>
+   The passed-in data will be copied into the cursor's portal, so it
+   can be freed while the cursor still exists.
+  </para>
  </refsect1>
 
  <refsect1>
@@ -1285,7 +1302,7 @@ Portal SPI_cursor_open(const char * <parameter>name</parameter>, void * <paramet
    </varlistentry>
 
    <varlistentry>
-    <term><literal>void * <parameter>plan</parameter></literal></term>
+    <term><literal>SPIPlanPtr <parameter>plan</parameter></literal></term>
     <listitem>
      <para>
       execution plan (returned by <function>SPI_prepare</function>)
@@ -1602,7 +1619,7 @@ void SPI_cursor_close(Portal <parameter>portal</parameter>)
 
  <refsynopsisdiv>
 <synopsis>
-void * SPI_saveplan(void * <parameter>plan</parameter>)
+SPIPlanPtr SPI_saveplan(SPIPlanPtr <parameter>plan</parameter>)
 </synopsis>
  </refsynopsisdiv>
 
@@ -1611,8 +1628,8 @@ void * SPI_saveplan(void * <parameter>plan</parameter>)
 
   <para>
    <function>SPI_saveplan</function> saves a passed plan (prepared by
-   <function>SPI_prepare</function>) in memory protected from freeing
-   by <function>SPI_finish</function> and by the transaction manager
+   <function>SPI_prepare</function>) in memory that will not be freed
+   by <function>SPI_finish</function> nor by the transaction manager,
    and returns a pointer to the saved plan.  This gives you the
    ability to reuse prepared plans in the subsequent invocations of
    your procedure in the current session.
@@ -1624,7 +1641,7 @@ void * SPI_saveplan(void * <parameter>plan</parameter>)
 
   <variablelist>
    <varlistentry>
-    <term><literal>void * <parameter>plan</parameter></literal></term>
+    <term><literal>SPIPlanPtr <parameter>plan</parameter></literal></term>
     <listitem>
      <para>
       the plan to be saved
@@ -1646,7 +1663,7 @@ void * SPI_saveplan(void * <parameter>plan</parameter>)
      <term><symbol>SPI_ERROR_ARGUMENT</symbol></term>
      <listitem>
       <para>
-       if <parameter>plan</parameter> is <symbol>NULL</symbol>
+       if <parameter>plan</parameter> is <symbol>NULL</symbol> or invalid
       </para>
      </listitem>
     </varlistentry>
@@ -1666,10 +1683,17 @@ void * SPI_saveplan(void * <parameter>plan</parameter>)
  <refsect1>
   <title>Notes</title>
 
+  <para>
+   The passed-in plan is not freed, so you might wish to do
+   <function>SPI_freeplan</function> on it to avoid leaking memory
+   until <function>SPI_finish</>.
+  </para>
+
   <para>
    If one of the objects (a table, function, etc.) referenced by the
-   prepared plan is dropped during the session then the results of
-   <function>SPI_execute_plan</function> for this plan will be unpredictable.
+   prepared plan is dropped or redefined, then future executions of
+   <function>SPI_execute_plan</function> may fail or return different
+   results than the plan initially indicates.
   </para>
  </refsect1>
 </refentry>
@@ -2879,7 +2903,7 @@ void SPI_freetuptable(SPITupleTable * <parameter>tuptable</parameter>)
 
  <refsynopsisdiv>
 <synopsis>
-int SPI_freeplan(void *<parameter>plan</parameter>)
+int SPI_freeplan(SPIPlanPtr <parameter>plan</parameter>)
 </synopsis>
  </refsynopsisdiv>
 
@@ -2898,7 +2922,7 @@ int SPI_freeplan(void *<parameter>plan</parameter>)
 
   <variablelist>
    <varlistentry>
-    <term><literal>void * <parameter>plan</parameter></literal></term>
+    <term><literal>SPIPlanPtr <parameter>plan</parameter></literal></term>
     <listitem>
      <para>
       pointer to plan to free
@@ -2913,7 +2937,7 @@ int SPI_freeplan(void *<parameter>plan</parameter>)
 
   <para>
    <symbol>SPI_ERROR_ARGUMENT</symbol> if <parameter>plan</parameter>
-   is <symbol>NULL</symbol>.
+   is <symbol>NULL</symbol> or invalid
   </para>
  </refsect1>
 </refentry>
index f538f508ba3f9a773b9c1251e6465ee150ffdba8..7a34add7105b27e69dfe08511434ad01971f1a86 100644 (file)
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/executor/spi.c,v 1.171 2007/03/13 00:33:40 tgl Exp $
+ *       $PostgreSQL: pgsql/src/backend/executor/spi.c,v 1.172 2007/03/15 23:12:06 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -34,9 +34,9 @@ static int    _SPI_stack_depth = 0;           /* allocated size of _SPI_stack */
 static int     _SPI_connected = -1;
 static int     _SPI_curid = -1;
 
-static void _SPI_prepare_plan(const char *src, _SPI_plan *plan);
+static void _SPI_prepare_plan(const char *src, SPIPlanPtr plan);
 
-static int _SPI_execute_plan(_SPI_plan *plan,
+static int _SPI_execute_plan(SPIPlanPtr plan,
                                  Datum *Values, const char *Nulls,
                                  Snapshot snapshot, Snapshot crosscheck_snapshot,
                                  bool read_only, long tcount);
@@ -48,7 +48,8 @@ static void _SPI_error_callback(void *arg);
 static void _SPI_cursor_operation(Portal portal, bool forward, long count,
                                          DestReceiver *dest);
 
-static _SPI_plan *_SPI_copy_plan(_SPI_plan *plan, int location);
+static SPIPlanPtr _SPI_copy_plan(SPIPlanPtr plan, MemoryContext parentcxt);
+static SPIPlanPtr _SPI_save_plan(SPIPlanPtr plan);
 
 static int     _SPI_begin_call(bool execmem);
 static int     _SPI_end_call(bool procmem);
@@ -306,10 +307,8 @@ SPI_execute(const char *src, bool read_only, long tcount)
        if (res < 0)
                return res;
 
-       plan.plancxt = NULL;            /* doesn't have own context */
-       plan.query = src;
-       plan.nargs = 0;
-       plan.argtypes = NULL;
+       memset(&plan, 0, sizeof(_SPI_plan));
+       plan.magic = _SPI_PLAN_MAGIC;
 
        _SPI_prepare_plan(src, &plan);
 
@@ -330,22 +329,22 @@ SPI_exec(const char *src, long tcount)
 
 /* Execute a previously prepared plan */
 int
-SPI_execute_plan(void *plan, Datum *Values, const char *Nulls,
+SPI_execute_plan(SPIPlanPtr plan, Datum *Values, const char *Nulls,
                                 bool read_only, long tcount)
 {
        int                     res;
 
-       if (plan == NULL || tcount < 0)
+       if (plan == NULL || plan->magic != _SPI_PLAN_MAGIC || tcount < 0)
                return SPI_ERROR_ARGUMENT;
 
-       if (((_SPI_plan *) plan)->nargs > 0 && Values == NULL)
+       if (plan->nargs > 0 && Values == NULL)
                return SPI_ERROR_PARAM;
 
        res = _SPI_begin_call(true);
        if (res < 0)
                return res;
 
-       res = _SPI_execute_plan((_SPI_plan *) plan,
+       res = _SPI_execute_plan(plan,
                                                        Values, Nulls,
                                                        InvalidSnapshot, InvalidSnapshot,
                                                        read_only, tcount);
@@ -356,7 +355,7 @@ SPI_execute_plan(void *plan, Datum *Values, const char *Nulls,
 
 /* Obsolete version of SPI_execute_plan */
 int
-SPI_execp(void *plan, Datum *Values, const char *Nulls, long tcount)
+SPI_execp(SPIPlanPtr plan, Datum *Values, const char *Nulls, long tcount)
 {
        return SPI_execute_plan(plan, Values, Nulls, false, tcount);
 }
@@ -371,24 +370,24 @@ SPI_execp(void *plan, Datum *Values, const char *Nulls, long tcount)
  * fetching a new snapshot for each query.
  */
 int
-SPI_execute_snapshot(void *plan,
+SPI_execute_snapshot(SPIPlanPtr plan,
                                         Datum *Values, const char *Nulls,
                                         Snapshot snapshot, Snapshot crosscheck_snapshot,
                                         bool read_only, long tcount)
 {
        int                     res;
 
-       if (plan == NULL || tcount < 0)
+       if (plan == NULL || plan->magic != _SPI_PLAN_MAGIC || tcount < 0)
                return SPI_ERROR_ARGUMENT;
 
-       if (((_SPI_plan *) plan)->nargs > 0 && Values == NULL)
+       if (plan->nargs > 0 && Values == NULL)
                return SPI_ERROR_PARAM;
 
        res = _SPI_begin_call(true);
        if (res < 0)
                return res;
 
-       res = _SPI_execute_plan((_SPI_plan *) plan,
+       res = _SPI_execute_plan(plan,
                                                        Values, Nulls,
                                                        snapshot, crosscheck_snapshot,
                                                        read_only, tcount);
@@ -397,11 +396,11 @@ SPI_execute_snapshot(void *plan,
        return res;
 }
 
-void *
+SPIPlanPtr
 SPI_prepare(const char *src, int nargs, Oid *argtypes)
 {
        _SPI_plan       plan;
-       _SPI_plan  *result;
+       SPIPlanPtr      result;
 
        if (src == NULL || nargs < 0 || (nargs > 0 && argtypes == NULL))
        {
@@ -413,27 +412,28 @@ SPI_prepare(const char *src, int nargs, Oid *argtypes)
        if (SPI_result < 0)
                return NULL;
 
-       plan.plancxt = NULL;            /* doesn't have own context */
-       plan.query = src;
+       memset(&plan, 0, sizeof(_SPI_plan));
+       plan.magic = _SPI_PLAN_MAGIC;
        plan.nargs = nargs;
        plan.argtypes = argtypes;
 
        _SPI_prepare_plan(src, &plan);
 
        /* copy plan to procedure context */
-       result = _SPI_copy_plan(&plan, _SPI_CPLAN_PROCXT);
+       result = _SPI_copy_plan(&plan, _SPI_current->procCxt);
 
        _SPI_end_call(true);
 
-       return (void *) result;
+       return result;
 }
 
-void *
-SPI_saveplan(void *plan)
+SPIPlanPtr
+SPI_saveplan(SPIPlanPtr plan)
 {
-       _SPI_plan  *newplan;
+       SPIPlanPtr      newplan;
 
-       if (plan == NULL)
+       /* We don't currently support copying an already-saved plan */
+       if (plan == NULL || plan->magic != _SPI_PLAN_MAGIC || plan->saved)
        {
                SPI_result = SPI_ERROR_ARGUMENT;
                return NULL;
@@ -443,23 +443,36 @@ SPI_saveplan(void *plan)
        if (SPI_result < 0)
                return NULL;
 
-       newplan = _SPI_copy_plan((_SPI_plan *) plan, _SPI_CPLAN_TOPCXT);
+       newplan = _SPI_save_plan(plan);
 
        _SPI_curid--;
        SPI_result = 0;
 
-       return (void *) newplan;
+       return newplan;
 }
 
 int
-SPI_freeplan(void *plan)
+SPI_freeplan(SPIPlanPtr plan)
 {
-       _SPI_plan  *spiplan = (_SPI_plan *) plan;
-
-       if (plan == NULL)
+       if (plan == NULL || plan->magic != _SPI_PLAN_MAGIC)
                return SPI_ERROR_ARGUMENT;
 
-       MemoryContextDelete(spiplan->plancxt);
+       /* If plancache.c owns the plancache entries, we must release them */
+       if (plan->saved)
+       {
+               ListCell   *lc;
+
+               foreach(lc, plan->plancache_list)
+               {
+                       CachedPlanSource *plansource = (CachedPlanSource *) lfirst(lc);
+
+                       DropCachedPlan(plansource);
+               }
+       }
+
+       /* Now get rid of the _SPI_plan and subsidiary data in its plancxt */
+       MemoryContextDelete(plan->plancxt);
+
        return 0;
 }
 
@@ -819,18 +832,18 @@ SPI_freetuptable(SPITupleTable *tuptable)
 }
 
 
-
 /*
  * SPI_cursor_open()
  *
  *     Open a prepared SPI plan as a portal
  */
 Portal
-SPI_cursor_open(const char *name, void *plan,
+SPI_cursor_open(const char *name, SPIPlanPtr plan,
                                Datum *Values, const char *Nulls,
                                bool read_only)
 {
-       _SPI_plan  *spiplan = (_SPI_plan *) plan;
+       CachedPlanSource *plansource;
+       CachedPlan *cplan;
        List       *stmt_list;
        ParamListInfo paramLI;
        Snapshot        snapshot;
@@ -842,25 +855,23 @@ SPI_cursor_open(const char *name, void *plan,
         * Check that the plan is something the Portal code will special-case as
         * returning one tupleset.
         */
-       if (!SPI_is_cursor_plan(spiplan))
+       if (!SPI_is_cursor_plan(plan))
        {
                /* try to give a good error message */
-               Node       *stmt;
-
-               if (list_length(spiplan->stmt_list_list) != 1)
+               if (list_length(plan->plancache_list) != 1)
                        ereport(ERROR,
                                        (errcode(ERRCODE_INVALID_CURSOR_DEFINITION),
                                         errmsg("cannot open multi-query plan as cursor")));
-               stmt = PortalListGetPrimaryStmt((List *) linitial(spiplan->stmt_list_list));
+               plansource = (CachedPlanSource *) linitial(plan->plancache_list);
                ereport(ERROR,
                                (errcode(ERRCODE_INVALID_CURSOR_DEFINITION),
                /* translator: %s is name of a SQL command, eg INSERT */
                                 errmsg("cannot open %s query as cursor",
-                                               CreateCommandTag(stmt))));
+                                               plansource->commandTag)));
        }
 
-       Assert(list_length(spiplan->stmt_list_list) == 1);
-       stmt_list = (List *) linitial(spiplan->stmt_list_list);
+       Assert(list_length(plan->plancache_list) == 1);
+       plansource = (CachedPlanSource *) linitial(plan->plancache_list);
 
        /* Reset SPI result (note we deliberately don't touch lastoid) */
        SPI_processed = 0;
@@ -880,23 +891,20 @@ SPI_cursor_open(const char *name, void *plan,
                portal = CreatePortal(name, false, false);
        }
 
-       /* Switch to portal's memory and copy the plans to there */
-       oldcontext = MemoryContextSwitchTo(PortalGetHeapMemory(portal));
-       stmt_list = copyObject(stmt_list);
-
-       /* If the plan has parameters, set them up */
-       if (spiplan->nargs > 0)
+       /* If the plan has parameters, copy them into the portal */
+       if (plan->nargs > 0)
        {
+               oldcontext = MemoryContextSwitchTo(PortalGetHeapMemory(portal));
                /* sizeof(ParamListInfoData) includes the first array element */
                paramLI = (ParamListInfo) palloc(sizeof(ParamListInfoData) +
-                                                         (spiplan->nargs - 1) *sizeof(ParamExternData));
-               paramLI->numParams = spiplan->nargs;
+                                                         (plan->nargs - 1) *sizeof(ParamExternData));
+               paramLI->numParams = plan->nargs;
 
-               for (k = 0; k < spiplan->nargs; k++)
+               for (k = 0; k < plan->nargs; k++)
                {
                        ParamExternData *prm = &paramLI->params[k];
 
-                       prm->ptype = spiplan->argtypes[k];
+                       prm->ptype = plan->argtypes[k];
                        prm->pflags = 0;
                        prm->isnull = (Nulls && Nulls[k] == 'n');
                        if (prm->isnull)
@@ -915,21 +923,35 @@ SPI_cursor_open(const char *name, void *plan,
                                                                           paramTypByVal, paramTypLen);
                        }
                }
+               MemoryContextSwitchTo(oldcontext);
        }
        else
                paramLI = NULL;
 
+       if (plan->saved)
+       {
+               /* Replan if needed, and increment plan refcount for portal */
+               cplan = RevalidateCachedPlan(plansource, false);
+               stmt_list = cplan->stmt_list;
+       }
+       else
+       {
+               /* No replan, but copy the plan into the portal's context */
+               oldcontext = MemoryContextSwitchTo(PortalGetHeapMemory(portal));
+               stmt_list = copyObject(plansource->plan->stmt_list);
+               MemoryContextSwitchTo(oldcontext);
+               cplan = NULL;                   /* portal shouldn't depend on cplan */
+       }
+
        /*
         * Set up the portal.
         */
        PortalDefineQuery(portal,
                                          NULL,         /* no statement name */
-                                         spiplan->query,
-                                         CreateCommandTag(PortalListGetPrimaryStmt(stmt_list)),
+                                         plansource->query_string,
+                                         plansource->commandTag,
                                          stmt_list,
-                                         NULL);
-
-       MemoryContextSwitchTo(oldcontext);
+                                         cplan);
 
        /*
         * Set up options for portal.
@@ -1023,28 +1045,29 @@ SPI_cursor_close(Portal portal)
  * parameter is at index zero.
  */
 Oid
-SPI_getargtypeid(void *plan, int argIndex)
+SPI_getargtypeid(SPIPlanPtr plan, int argIndex)
 {
-       if (plan == NULL || argIndex < 0 || argIndex >= ((_SPI_plan *) plan)->nargs)
+       if (plan == NULL || plan->magic != _SPI_PLAN_MAGIC ||
+               argIndex < 0 || argIndex >= plan->nargs)
        {
                SPI_result = SPI_ERROR_ARGUMENT;
                return InvalidOid;
        }
-       return ((_SPI_plan *) plan)->argtypes[argIndex];
+       return plan->argtypes[argIndex];
 }
 
 /*
  * Returns the number of arguments for the prepared plan.
  */
 int
-SPI_getargcount(void *plan)
+SPI_getargcount(SPIPlanPtr plan)
 {
-       if (plan == NULL)
+       if (plan == NULL || plan->magic != _SPI_PLAN_MAGIC)
        {
                SPI_result = SPI_ERROR_ARGUMENT;
                return -1;
        }
-       return ((_SPI_plan *) plan)->nargs;
+       return plan->nargs;
 }
 
 /*
@@ -1057,31 +1080,32 @@ SPI_getargcount(void *plan)
  *       plan: A plan previously prepared using SPI_prepare
  */
 bool
-SPI_is_cursor_plan(void *plan)
+SPI_is_cursor_plan(SPIPlanPtr plan)
 {
-       _SPI_plan  *spiplan = (_SPI_plan *) plan;
+       CachedPlanSource *plansource;
+       CachedPlan *cplan;
 
-       if (spiplan == NULL)
+       if (plan == NULL || plan->magic != _SPI_PLAN_MAGIC)
        {
                SPI_result = SPI_ERROR_ARGUMENT;
                return false;
        }
 
-       if (list_length(spiplan->stmt_list_list) != 1)
+       if (list_length(plan->plancache_list) != 1)
                return false;                   /* not exactly 1 pre-rewrite command */
+       plansource = (CachedPlanSource *) linitial(plan->plancache_list);
 
-       switch (ChoosePortalStrategy((List *) linitial(spiplan->stmt_list_list)))
+       if (plan->saved)
        {
-               case PORTAL_ONE_SELECT:
-               case PORTAL_ONE_RETURNING:
-               case PORTAL_UTIL_SELECT:
-                       /* OK */
-                       return true;
-
-               case PORTAL_MULTI_QUERY:
-                       /* will not return tuples */
-                       break;
+               /* Make sure the plan is up to date */
+               cplan = RevalidateCachedPlan(plansource, true);
+               ReleaseCachedPlan(cplan, true);
        }
+
+       /* Does it return tuples? */
+       if (plansource->resultDesc)
+               return true;
+
        return false;
 }
 
@@ -1248,13 +1272,15 @@ spi_printtup(TupleTableSlot *slot, DestReceiver *self)
  *
  * At entry, plan->argtypes and plan->nargs must be valid.
  *
- * Result lists are stored into *plan.
+ * Results are stored into *plan (specifically, plan->plancache_list).
+ * Note however that the result trees are all in CurrentMemoryContext
+ * and need to be copied somewhere to survive.
  */
 static void
-_SPI_prepare_plan(const char *src, _SPI_plan *plan)
+_SPI_prepare_plan(const char *src, SPIPlanPtr plan)
 {
        List       *raw_parsetree_list;
-       List       *stmt_list_list;
+       List       *plancache_list;
        ListCell   *list_item;
        ErrorContextCallback spierrcontext;
        Oid                *argtypes = plan->argtypes;
@@ -1282,26 +1308,44 @@ _SPI_prepare_plan(const char *src, _SPI_plan *plan)
        raw_parsetree_list = pg_parse_query(src);
 
        /*
-        * Do parse analysis and rule rewrite for each raw parsetree.
-        *
-        * We save the results from each raw parsetree as a separate sublist.
-        * This allows _SPI_execute_plan() to know where the boundaries between
-        * original queries fall.
+        * Do parse analysis and rule rewrite for each raw parsetree, then
+        * cons up a phony plancache entry for each one.
         */
-       stmt_list_list = NIL;
+       plancache_list = NIL;
 
        foreach(list_item, raw_parsetree_list)
        {
                Node       *parsetree = (Node *) lfirst(list_item);
-               List       *query_list;
-
-               query_list = pg_analyze_and_rewrite(parsetree, src, argtypes, nargs);
-
-               stmt_list_list = lappend(stmt_list_list,
-                                                                pg_plan_queries(query_list, NULL, false));
+               List       *stmt_list;
+               CachedPlanSource *plansource;
+               CachedPlan *cplan;
+
+               /* Need a copyObject here to keep parser from modifying raw tree */
+               stmt_list = pg_analyze_and_rewrite(copyObject(parsetree),
+                                                                                  src, argtypes, nargs);
+               stmt_list = pg_plan_queries(stmt_list, NULL, false);
+
+               plansource = (CachedPlanSource *) palloc0(sizeof(CachedPlanSource));
+               cplan = (CachedPlan *) palloc0(sizeof(CachedPlan));
+
+           plansource->raw_parse_tree = parsetree;
+               /* cast-away-const here is a bit ugly, but there's no reason to copy */
+           plansource->query_string = (char *) src;
+               plansource->commandTag = CreateCommandTag(parsetree);
+               plansource->param_types = argtypes;
+               plansource->num_params = nargs;
+               plansource->fully_planned = true;
+               plansource->fixed_result = false;
+               plansource->resultDesc = PlanCacheComputeResultDesc(stmt_list);
+               plansource->plan = cplan;
+
+               cplan->stmt_list = stmt_list;
+               cplan->fully_planned = true;
+
+               plancache_list = lappend(plancache_list, plansource);
        }
 
-       plan->stmt_list_list = stmt_list_list;
+       plan->plancache_list = plancache_list;
 
        /*
         * Pop the error context stack
@@ -1319,7 +1363,7 @@ _SPI_prepare_plan(const char *src, _SPI_plan *plan)
  * tcount: execution tuple-count limit, or 0 for none
  */
 static int
-_SPI_execute_plan(_SPI_plan *plan, Datum *Values, const char *Nulls,
+_SPI_execute_plan(SPIPlanPtr plan, Datum *Values, const char *Nulls,
                                  Snapshot snapshot, Snapshot crosscheck_snapshot,
                                  bool read_only, long tcount)
 {
@@ -1334,10 +1378,11 @@ _SPI_execute_plan(_SPI_plan *plan, Datum *Values, const char *Nulls,
        saveActiveSnapshot = ActiveSnapshot;
        PG_TRY();
        {
-               ListCell   *stmt_list_list_item;
+               ListCell   *lc1;
                ErrorContextCallback spierrcontext;
                int                     nargs = plan->nargs;
                ParamListInfo paramLI;
+               CachedPlan *cplan = NULL;
 
                /* Convert parameters to form wanted by executor */
                if (nargs > 0)
@@ -1366,18 +1411,34 @@ _SPI_execute_plan(_SPI_plan *plan, Datum *Values, const char *Nulls,
                 * Setup error traceback support for ereport()
                 */
                spierrcontext.callback = _SPI_error_callback;
-               spierrcontext.arg = (void *) plan->query;
+               spierrcontext.arg = NULL;
                spierrcontext.previous = error_context_stack;
                error_context_stack = &spierrcontext;
 
-               foreach(stmt_list_list_item, plan->stmt_list_list)
+               foreach(lc1, plan->plancache_list)
                {
-                       List       *stmt_list = (List *) lfirst(stmt_list_list_item);
-                       ListCell   *stmt_list_item;
+                       CachedPlanSource *plansource = (CachedPlanSource *) lfirst(lc1);
+                       List       *stmt_list;
+                       ListCell   *lc2;
 
-                       foreach(stmt_list_item, stmt_list)
+                       spierrcontext.arg = (void *) plansource->query_string;
+
+                       if (plan->saved)
                        {
-                               Node       *stmt = (Node *) lfirst(stmt_list_item);
+                               /* Replan if needed, and increment plan refcount locally */
+                               cplan = RevalidateCachedPlan(plansource, true);
+                               stmt_list = cplan->stmt_list;
+                       }
+                       else
+                       {
+                               /* No replan here */
+                               cplan = NULL;
+                               stmt_list = plansource->plan->stmt_list;
+                       }
+
+                       foreach(lc2, stmt_list)
+                       {
+                               Node       *stmt = (Node *) lfirst(lc2);
                                bool            canSetTag;
                                QueryDesc  *qdesc;
                                DestReceiver *dest;
@@ -1510,10 +1571,19 @@ _SPI_execute_plan(_SPI_plan *plan, Datum *Values, const char *Nulls,
                                        goto fail;
                                }
                        }
+
+                       /* Done with this plan, so release refcount */
+                       if (cplan)
+                               ReleaseCachedPlan(cplan, true);
+                       cplan = NULL;
                }
 
 fail:
 
+               /* We no longer need the cached plan refcount, if any */
+               if (cplan)
+                       ReleaseCachedPlan(cplan, true);
+
                /*
                 * Pop the error context stack
                 */
@@ -1772,22 +1842,18 @@ _SPI_checktuples(void)
        return failed;
 }
 
-static _SPI_plan *
-_SPI_copy_plan(_SPI_plan *plan, int location)
+/*
+ * Make an "unsaved" copy of the given plan, in a child context of parentcxt.
+ */
+static SPIPlanPtr
+_SPI_copy_plan(SPIPlanPtr plan, MemoryContext parentcxt)
 {
-       _SPI_plan  *newplan;
-       MemoryContext oldcxt;
+       SPIPlanPtr      newplan;
        MemoryContext plancxt;
-       MemoryContext parentcxt;
+       MemoryContext oldcxt;
+       ListCell   *lc;
 
-       /* Determine correct parent for the plan's memory context */
-       if (location == _SPI_CPLAN_PROCXT)
-               parentcxt = _SPI_current->procCxt;
-       else if (location == _SPI_CPLAN_TOPCXT)
-               parentcxt = TopMemoryContext;
-       else
-               /* (this case not currently used) */
-               parentcxt = CurrentMemoryContext;
+       Assert(!plan->saved);           /* not currently supported */
 
        /*
         * Create a memory context for the plan.  We don't expect the plan to be
@@ -1801,10 +1867,11 @@ _SPI_copy_plan(_SPI_plan *plan, int location)
        oldcxt = MemoryContextSwitchTo(plancxt);
 
        /* Copy the SPI plan into its own context */
-       newplan = (_SPI_plan *) palloc(sizeof(_SPI_plan));
+       newplan = (SPIPlanPtr) palloc(sizeof(_SPI_plan));
+       newplan->magic = _SPI_PLAN_MAGIC;
+       newplan->saved = false;
+       newplan->plancache_list = NIL;
        newplan->plancxt = plancxt;
-       newplan->query = pstrdup(plan->query);
-       newplan->stmt_list_list = (List *) copyObject(plan->stmt_list_list);
        newplan->nargs = plan->nargs;
        if (plan->nargs > 0)
        {
@@ -1814,6 +1881,101 @@ _SPI_copy_plan(_SPI_plan *plan, int location)
        else
                newplan->argtypes = NULL;
 
+       foreach(lc, plan->plancache_list)
+       {
+               CachedPlanSource *plansource = (CachedPlanSource *) lfirst(lc);
+               CachedPlanSource *newsource;
+               CachedPlan *cplan;
+               CachedPlan *newcplan;
+
+               /* Note: we assume we don't need to revalidate the plan */
+               cplan = plansource->plan;
+
+               newsource = (CachedPlanSource *) palloc0(sizeof(CachedPlanSource));
+               newcplan = (CachedPlan *) palloc0(sizeof(CachedPlan));
+
+           newsource->raw_parse_tree = copyObject(plansource->raw_parse_tree);
+           newsource->query_string = pstrdup(plansource->query_string);
+               newsource->commandTag = plansource->commandTag;
+               newsource->param_types = newplan->argtypes;
+               newsource->num_params = newplan->nargs;
+               newsource->fully_planned = plansource->fully_planned;
+               newsource->fixed_result = plansource->fixed_result;
+               if (plansource->resultDesc)
+                       newsource->resultDesc = CreateTupleDescCopy(plansource->resultDesc);
+               newsource->plan = newcplan;
+
+               newcplan->stmt_list = copyObject(cplan->stmt_list);
+               newcplan->fully_planned = cplan->fully_planned;
+
+               newplan->plancache_list = lappend(newplan->plancache_list, newsource);
+       }
+
+       MemoryContextSwitchTo(oldcxt);
+
+       return newplan;
+}
+
+/*
+ * Make a "saved" copy of the given plan, entrusting everything to plancache.c
+ */
+static SPIPlanPtr
+_SPI_save_plan(SPIPlanPtr plan)
+{
+       SPIPlanPtr      newplan;
+       MemoryContext plancxt;
+       MemoryContext oldcxt;
+       ListCell   *lc;
+
+       Assert(!plan->saved);           /* not currently supported */
+
+       /*
+        * Create a memory context for the plan.  We don't expect the plan to be
+        * very large, so use smaller-than-default alloc parameters.
+        */
+       plancxt = AllocSetContextCreate(CacheMemoryContext,
+                                                                       "SPI Plan",
+                                                                       ALLOCSET_SMALL_MINSIZE,
+                                                                       ALLOCSET_SMALL_INITSIZE,
+                                                                       ALLOCSET_SMALL_MAXSIZE);
+       oldcxt = MemoryContextSwitchTo(plancxt);
+
+       /* Copy the SPI plan into its own context */
+       newplan = (SPIPlanPtr) palloc(sizeof(_SPI_plan));
+       newplan->magic = _SPI_PLAN_MAGIC;
+       newplan->saved = true;
+       newplan->plancache_list = NIL;
+       newplan->plancxt = plancxt;
+       newplan->nargs = plan->nargs;
+       if (plan->nargs > 0)
+       {
+               newplan->argtypes = (Oid *) palloc(plan->nargs * sizeof(Oid));
+               memcpy(newplan->argtypes, plan->argtypes, plan->nargs * sizeof(Oid));
+       }
+       else
+               newplan->argtypes = NULL;
+
+       foreach(lc, plan->plancache_list)
+       {
+               CachedPlanSource *plansource = (CachedPlanSource *) lfirst(lc);
+               CachedPlanSource *newsource;
+               CachedPlan *cplan;
+
+               /* Note: we assume we don't need to revalidate the plan */
+               cplan = plansource->plan;
+
+               newsource = CreateCachedPlan(plansource->raw_parse_tree,
+                                                                        plansource->query_string,
+                                                                        plansource->commandTag,
+                                                                        newplan->argtypes,
+                                                                        newplan->nargs,
+                                                                        cplan->stmt_list,
+                                                                        true,
+                                                                        false);
+
+               newplan->plancache_list = lappend(newplan->plancache_list, newsource);
+       }
+
        MemoryContextSwitchTo(oldcxt);
 
        return newplan;
index 4ba2bb7a98f05f1dc36f96e92bcf00e4c8c646d3..72200ced9dcc0527d79fa596da8a6c9809953afe 100644 (file)
@@ -8,16 +8,14 @@
  *     across query and transaction boundaries, in fact they live as long as
  *     the backend does.  This works because the hashtable structures
  *     themselves are allocated by dynahash.c in its permanent DynaHashCxt,
- *     and the parse/plan node trees they point to are copied into
- *     TopMemoryContext using SPI_saveplan().  This is pretty ugly, since there
- *     is no way to free a no-longer-needed plan tree, but then again we don't
- *     yet have any bookkeeping that would allow us to detect that a plan isn't
- *     needed anymore.  Improve it someday.
+ *     and the SPI plans they point to are saved using SPI_saveplan().
+ *     There is not currently any provision for throwing away a no-longer-needed
+ *     plan --- consider improving this someday.
  *
  *
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/backend/utils/adt/ri_triggers.c,v 1.91 2007/02/14 01:58:57 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/ri_triggers.c,v 1.92 2007/03/15 23:12:06 tgl Exp $
  *
  * ----------
  */
@@ -35,7 +33,7 @@
 #include "catalog/pg_constraint.h"
 #include "catalog/pg_operator.h"
 #include "commands/trigger.h"
-#include "executor/spi_priv.h"
+#include "executor/spi.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_relation.h"
 #include "miscadmin.h"
@@ -135,7 +133,7 @@ typedef struct RI_QueryKey
 typedef struct RI_QueryHashEntry
 {
        RI_QueryKey key;
-       void       *plan;
+       SPIPlanPtr      plan;
 } RI_QueryHashEntry;
 
 
@@ -206,18 +204,18 @@ static bool ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
                                  const RI_ConstraintInfo *riinfo);
 
 static void ri_InitHashTables(void);
-static void *ri_FetchPreparedPlan(RI_QueryKey *key);
-static void ri_HashPreparedPlan(RI_QueryKey *key, void *plan);
+static SPIPlanPtr ri_FetchPreparedPlan(RI_QueryKey *key);
+static void ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan);
 static RI_CompareHashEntry *ri_HashCompareOp(Oid eq_opr, Oid typeid);
 
 static void ri_CheckTrigger(FunctionCallInfo fcinfo, const char *funcname,
                                int tgkind);
 static void ri_FetchConstraintInfo(RI_ConstraintInfo *riinfo,
                                           Trigger *trigger, Relation trig_rel, bool rel_is_pk);
-static void *ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
+static SPIPlanPtr ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
                         RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel,
                         bool cache_plan);
-static bool ri_PerformCheck(RI_QueryKey *qkey, void *qplan,
+static bool ri_PerformCheck(RI_QueryKey *qkey, SPIPlanPtr qplan,
                                Relation fk_rel, Relation pk_rel,
                                HeapTuple old_tuple, HeapTuple new_tuple,
                                bool detectNewRows,
@@ -248,7 +246,7 @@ RI_FKey_check(PG_FUNCTION_ARGS)
        HeapTuple       old_row;
        Buffer          new_row_buf;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
        int                     i;
 
        /*
@@ -542,7 +540,7 @@ ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
                                  HeapTuple old_row,
                                  const RI_ConstraintInfo *riinfo)
 {
-       void       *qplan;
+       SPIPlanPtr      qplan;
        RI_QueryKey qkey;
        int                     i;
        bool            result;
@@ -678,7 +676,7 @@ RI_FKey_noaction_del(PG_FUNCTION_ARGS)
        Relation        pk_rel;
        HeapTuple       old_row;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
        int                     i;
 
        /*
@@ -855,7 +853,7 @@ RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
        HeapTuple       new_row;
        HeapTuple       old_row;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
        int                     i;
 
        /*
@@ -1040,7 +1038,7 @@ RI_FKey_cascade_del(PG_FUNCTION_ARGS)
        Relation        pk_rel;
        HeapTuple       old_row;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
        int                     i;
 
        /*
@@ -1203,7 +1201,7 @@ RI_FKey_cascade_upd(PG_FUNCTION_ARGS)
        HeapTuple       new_row;
        HeapTuple       old_row;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
        int                     i;
        int                     j;
 
@@ -1397,7 +1395,7 @@ RI_FKey_restrict_del(PG_FUNCTION_ARGS)
        Relation        pk_rel;
        HeapTuple       old_row;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
        int                     i;
 
        /*
@@ -1569,7 +1567,7 @@ RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
        HeapTuple       new_row;
        HeapTuple       old_row;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
        int                     i;
 
        /*
@@ -1744,7 +1742,7 @@ RI_FKey_setnull_del(PG_FUNCTION_ARGS)
        Relation        pk_rel;
        HeapTuple       old_row;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
        int                     i;
 
        /*
@@ -1916,7 +1914,7 @@ RI_FKey_setnull_upd(PG_FUNCTION_ARGS)
        HeapTuple       new_row;
        HeapTuple       old_row;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
        int                     i;
        bool            use_cached_query;
 
@@ -2130,7 +2128,7 @@ RI_FKey_setdefault_del(PG_FUNCTION_ARGS)
        Relation        pk_rel;
        HeapTuple       old_row;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
 
        /*
         * Check that this is a valid trigger call on the right time and event.
@@ -2313,7 +2311,7 @@ RI_FKey_setdefault_upd(PG_FUNCTION_ARGS)
        HeapTuple       new_row;
        HeapTuple       old_row;
        RI_QueryKey qkey;
-       void       *qplan;
+       SPIPlanPtr      qplan;
 
        /*
         * Check that this is a valid trigger call on the right time and event.
@@ -2637,7 +2635,7 @@ RI_Initial_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
        int                     old_work_mem;
        char            workmembuf[32];
        int                     spi_result;
-       void       *qplan;
+       SPIPlanPtr      qplan;
 
        /*
         * Check to make sure current user has enough permissions to do the test
@@ -3165,12 +3163,12 @@ ri_FetchConstraintInfo(RI_ConstraintInfo *riinfo,
  * If cache_plan is true, the plan is saved into our plan hashtable
  * so that we don't need to plan it again.
  */
-static void *
+static SPIPlanPtr
 ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
                         RI_QueryKey *qkey, Relation fk_rel, Relation pk_rel,
                         bool cache_plan)
 {
-       void       *qplan;
+       SPIPlanPtr      qplan;
        Relation        query_rel;
        Oid                     save_uid;
 
@@ -3212,7 +3210,7 @@ ri_PlanCheck(const char *querystr, int nargs, Oid *argtypes,
  * Perform a query to enforce an RI restriction
  */
 static bool
-ri_PerformCheck(RI_QueryKey *qkey, void *qplan,
+ri_PerformCheck(RI_QueryKey *qkey, SPIPlanPtr qplan,
                                Relation fk_rel, Relation pk_rel,
                                HeapTuple old_tuple, HeapTuple new_tuple,
                                bool detectNewRows,
@@ -3576,7 +3574,7 @@ ri_InitHashTables(void)
  *     and saved SPI execution plans. Return the plan if found or NULL.
  * ----------
  */
-static void *
+static SPIPlanPtr
 ri_FetchPreparedPlan(RI_QueryKey *key)
 {
        RI_QueryHashEntry *entry;
@@ -3606,7 +3604,7 @@ ri_FetchPreparedPlan(RI_QueryKey *key)
  * ----------
  */
 static void
-ri_HashPreparedPlan(RI_QueryKey *key, void *plan)
+ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan)
 {
        RI_QueryHashEntry *entry;
        bool            found;
index f17061738a4a8d3ac9a1d1e517025d7d4c3338bf..9ec0aa56f0aa201c6727f29a72656aeb26fbbea1 100644 (file)
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.252 2007/02/27 23:48:08 tgl Exp $
+ *       $PostgreSQL: pgsql/src/backend/utils/adt/ruleutils.c,v 1.253 2007/03/15 23:12:06 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -105,9 +105,9 @@ typedef struct
  * Global data
  * ----------
  */
-static void *plan_getrulebyoid = NULL;
+static SPIPlanPtr plan_getrulebyoid = NULL;
 static char *query_getrulebyoid = "SELECT * FROM pg_catalog.pg_rewrite WHERE oid = $1";
-static void *plan_getviewrule = NULL;
+static SPIPlanPtr plan_getviewrule = NULL;
 static char *query_getviewrule = "SELECT * FROM pg_catalog.pg_rewrite WHERE ev_class = $1 AND rulename = $2";
 
 
@@ -250,7 +250,7 @@ pg_get_ruledef_worker(Oid ruleoid, int prettyFlags)
        if (plan_getrulebyoid == NULL)
        {
                Oid                     argtypes[1];
-               void       *plan;
+               SPIPlanPtr      plan;
 
                argtypes[0] = OIDOID;
                plan = SPI_prepare(query_getrulebyoid, 1, argtypes);
@@ -380,7 +380,7 @@ pg_get_viewdef_worker(Oid viewoid, int prettyFlags)
        if (plan_getviewrule == NULL)
        {
                Oid                     argtypes[2];
-               void       *plan;
+               SPIPlanPtr      plan;
 
                argtypes[0] = OIDOID;
                argtypes[1] = NAMEOID;
index 921fe1d9f50d19ea18897fe84456ccc88497a6a8..fa82837fd0cce6a64042decd83152e6d42e972e4 100644 (file)
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/backend/utils/adt/xml.c,v 1.34 2007/03/03 19:32:55 neilc Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/xml.c,v 1.35 2007/03/15 23:12:06 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1800,7 +1800,7 @@ query_to_xmlschema(PG_FUNCTION_ARGS)
        const char *targetns = _textout(PG_GETARG_TEXT_P(3));
 
        const char *result;
-       void       *plan;
+       SPIPlanPtr      plan;
        Portal          portal;
 
        SPI_connect();
@@ -1871,7 +1871,7 @@ query_to_xml_and_xmlschema(PG_FUNCTION_ARGS)
        const char *targetns = _textout(PG_GETARG_TEXT_P(3));
 
        const char *xmlschema;
-       void       *plan;
+       SPIPlanPtr      plan;
        Portal          portal;
 
        SPI_connect();
index 95ed49818cbc51e46deb3b3f9457aaffa7fa0fa8..61a576d35d981928d9baade9ec64955729cdb8f9 100644 (file)
@@ -33,7 +33,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/utils/cache/plancache.c,v 1.1 2007/03/13 00:33:42 tgl Exp $
+ *       $PostgreSQL: pgsql/src/backend/utils/cache/plancache.c,v 1.2 2007/03/15 23:12:06 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -77,7 +77,6 @@ static void ScanQueryForRelids(Query *parsetree,
                                                           void *arg);
 static bool ScanQueryWalker(Node *node, ScanQueryWalkerContext *context);
 static bool rowmark_member(List *rowMarks, int rt_index);
-static TupleDesc ComputeResultDesc(List *stmt_list);
 static void PlanCacheCallback(Datum arg, Oid relid);
 static void InvalRelid(Oid relid, LOCKMODE lockmode,
                                           InvalRelidContext *context);
@@ -153,7 +152,7 @@ CreateCachedPlan(Node *raw_parse_tree,
        plansource->fully_planned = fully_planned;
        plansource->fixed_result = fixed_result;
        plansource->generation = 0;                     /* StoreCachedPlan will increment */
-       plansource->resultDesc = ComputeResultDesc(stmt_list);
+       plansource->resultDesc = PlanCacheComputeResultDesc(stmt_list);
        plansource->plan = NULL;
        plansource->context = source_context;
        plansource->orig_plan = NULL;
@@ -225,7 +224,7 @@ FastCreateCachedPlan(Node *raw_parse_tree,
        plansource->fully_planned = fully_planned;
        plansource->fixed_result = fixed_result;
        plansource->generation = 0;                     /* StoreCachedPlan will increment */
-       plansource->resultDesc = ComputeResultDesc(stmt_list);
+       plansource->resultDesc = PlanCacheComputeResultDesc(stmt_list);
        plansource->plan = NULL;
        plansource->context = context;
        plansource->orig_plan = NULL;
@@ -271,12 +270,13 @@ StoreCachedPlan(CachedPlanSource *plansource,
        {
                /*
                 * Make a dedicated memory context for the CachedPlan and its
-                * subsidiary data.
+                * subsidiary data.  It's probably not going to be large, but
+                * just in case, use the default maxsize parameter.
                 */
                plan_context = AllocSetContextCreate(CacheMemoryContext,
                                                                                         "CachedPlan",
-                                                                                        ALLOCSET_DEFAULT_MINSIZE,
-                                                                                        ALLOCSET_DEFAULT_INITSIZE,
+                                                                                        ALLOCSET_SMALL_MINSIZE,
+                                                                                        ALLOCSET_SMALL_INITSIZE,
                                                                                         ALLOCSET_DEFAULT_MAXSIZE);
 
                /*
@@ -445,7 +445,7 @@ RevalidateCachedPlan(CachedPlanSource *plansource, bool useResOwner)
                 * Check or update the result tupdesc.  XXX should we use a weaker
                 * condition than equalTupleDescs() here?
                 */
-               resultDesc = ComputeResultDesc(slist);
+               resultDesc = PlanCacheComputeResultDesc(slist);
                if (resultDesc == NULL && plansource->resultDesc == NULL)
                {
                        /* OK, doesn't return tuples */
@@ -718,14 +718,14 @@ rowmark_member(List *rowMarks, int rt_index)
 }
 
 /*
- * ComputeResultDesc: given a list of either fully-planned statements or
- * Queries, determine the result tupledesc it will produce.  Returns NULL
+ * PlanCacheComputeResultDesc: given a list of either fully-planned statements
+ * or Queries, determine the result tupledesc it will produce.  Returns NULL
  * if the execution will not return tuples.
  *
  * Note: the result is created or copied into current memory context.
  */
-static TupleDesc
-ComputeResultDesc(List *stmt_list)
+TupleDesc
+PlanCacheComputeResultDesc(List *stmt_list)
 {
        Node       *node;
        Query      *query;
index 9cbbc035dcc7b859eb20bf9de1d887c8d101a2bd..c041726a45a3aab0bfb06560df8f8a18173cf19d 100644 (file)
@@ -1,8 +1,12 @@
 /*-------------------------------------------------------------------------
  *
  * spi.h
+ *                             Server Programming Interface public declarations
  *
- * $PostgreSQL: pgsql/src/include/executor/spi.h,v 1.58 2006/10/04 00:30:08 momjian Exp $
+ * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * $PostgreSQL: pgsql/src/include/executor/spi.h,v 1.59 2007/03/15 23:12:06 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -24,6 +28,7 @@
 #include "catalog/pg_language.h"
 #include "catalog/pg_proc.h"
 #include "catalog/pg_type.h"
+#include "executor/execdefs.h"
 #include "executor/executor.h"
 #include "nodes/execnodes.h"
 #include "nodes/params.h"
@@ -38,9 +43,9 @@
 #include "utils/datum.h"
 #include "utils/portal.h"
 #include "utils/syscache.h"
-#include "executor/execdefs.h"
 
-typedef struct
+
+typedef struct SPITupleTable
 {
        MemoryContext tuptabcxt;        /* memory context of result table */
        uint32          alloced;                /* # of alloced vals */
@@ -49,6 +54,9 @@ typedef struct
        HeapTuple  *vals;                       /* tuples */
 } SPITupleTable;
 
+/* Plans are opaque structs for standard users of SPI */
+typedef struct _SPI_plan *SPIPlanPtr;
+
 #define SPI_ERROR_CONNECT              (-1)
 #define SPI_ERROR_COPY                 (-2)
 #define SPI_ERROR_OPUNKNOWN            (-3)
@@ -86,23 +94,23 @@ extern void SPI_push(void);
 extern void SPI_pop(void);
 extern void SPI_restore_connection(void);
 extern int     SPI_execute(const char *src, bool read_only, long tcount);
-extern int SPI_execute_plan(void *plan, Datum *Values, const char *Nulls,
+extern int     SPI_execute_plan(SPIPlanPtr plan, Datum *Values, const char *Nulls,
                                 bool read_only, long tcount);
 extern int     SPI_exec(const char *src, long tcount);
-extern int SPI_execp(void *plan, Datum *Values, const char *Nulls,
+extern int     SPI_execp(SPIPlanPtr plan, Datum *Values, const char *Nulls,
                  long tcount);
-extern int SPI_execute_snapshot(void *plan,
+extern int     SPI_execute_snapshot(SPIPlanPtr plan,
                                         Datum *Values, const char *Nulls,
                                         Snapshot snapshot,
                                         Snapshot crosscheck_snapshot,
                                         bool read_only, long tcount);
-extern void *SPI_prepare(const char *src, int nargs, Oid *argtypes);
-extern void *SPI_saveplan(void *plan);
-extern int     SPI_freeplan(void *plan);
+extern SPIPlanPtr SPI_prepare(const char *src, int nargs, Oid *argtypes);
+extern SPIPlanPtr SPI_saveplan(SPIPlanPtr plan);
+extern int     SPI_freeplan(SPIPlanPtr plan);
 
-extern Oid     SPI_getargtypeid(void *plan, int argIndex);
-extern int     SPI_getargcount(void *plan);
-extern bool SPI_is_cursor_plan(void *plan);
+extern Oid     SPI_getargtypeid(SPIPlanPtr plan, int argIndex);
+extern int     SPI_getargcount(SPIPlanPtr plan);
+extern bool SPI_is_cursor_plan(SPIPlanPtr plan);
 extern const char *SPI_result_code_string(int code);
 
 extern HeapTuple SPI_copytuple(HeapTuple tuple);
@@ -123,7 +131,7 @@ extern void SPI_pfree(void *pointer);
 extern void SPI_freetuple(HeapTuple pointer);
 extern void SPI_freetuptable(SPITupleTable *tuptable);
 
-extern Portal SPI_cursor_open(const char *name, void *plan,
+extern Portal SPI_cursor_open(const char *name, SPIPlanPtr plan,
                                Datum *Values, const char *Nulls, bool read_only);
 extern Portal SPI_cursor_find(const char *name);
 extern void SPI_cursor_fetch(Portal portal, bool forward, long count);
index 5e65bd750aeaaeba4dbc8639b4a4398a92603751..7ce7d0b098308f4dcd25e443ea49e84ede113628 100644 (file)
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/executor/spi_priv.h,v 1.27 2007/02/20 17:32:17 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/executor/spi_priv.h,v 1.28 2007/03/15 23:12:07 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -16,6 +16,8 @@
 #include "executor/spi.h"
 
 
+#define _SPI_PLAN_MAGIC                569278163
+
 typedef struct
 {
        /* current results */
@@ -25,29 +27,46 @@ typedef struct
 
        MemoryContext procCxt;          /* procedure context */
        MemoryContext execCxt;          /* executor context */
-       MemoryContext savedcxt;
+       MemoryContext savedcxt;         /* context of SPI_connect's caller */
        SubTransactionId connectSubid;          /* ID of connecting subtransaction */
 } _SPI_connection;
 
-typedef struct
+/*
+ * SPI plans have two states: saved or unsaved.
+ *
+ * For an unsaved plan, the _SPI_plan struct and all its subsidiary data are in
+ * a dedicated memory context identified by plancxt.  An unsaved plan is good
+ * at most for the current transaction, since the locks that protect it from
+ * schema changes will be lost at end of transaction.  Hence the plancxt is
+ * always a transient one.
+ *
+ * For a saved plan, the _SPI_plan struct and the argument type array are in
+ * the plancxt (which can be really small).  All the other subsidiary state
+ * is in plancache entries identified by plancache_list (note: the list cells
+ * themselves are in plancxt).  We rely on plancache.c to keep the cache
+ * entries up-to-date as needed.  The plancxt is a child of CacheMemoryContext
+ * since it should persist until explicitly destroyed.
+ *
+ * To avoid redundant coding, the representation of unsaved plans matches
+ * that of saved plans, ie, plancache_list is a list of CachedPlanSource
+ * structs which in turn point to CachedPlan structs.  However, in an unsaved
+ * plan all these structs are just created by spi.c and are not known to
+ * plancache.c.  We don't try very hard to make all their fields valid,
+ * only the ones spi.c actually uses.
+ *
+ * Note: if the original query string contained only whitespace and comments,
+ * the plancache_list will be NIL and so there is no place to store the
+ * query string.  We don't care about that, but we do care about the
+ * argument type array, which is why it's seemingly-redundantly stored.
+ */
+typedef struct _SPI_plan
 {
-       /* Context containing _SPI_plan itself as well as subsidiary data */
-       MemoryContext plancxt;
-       /* Original query string (used for error reporting) */
-       const char *query;
-       /*
-        * List of List of PlannedStmts and utility stmts; one sublist per
-        * original parsetree
-        */
-       List       *stmt_list_list;
-       /* Argument types, if a prepared plan */
-       int                     nargs;
-       Oid                *argtypes;
+       int                     magic;                  /* should equal _SPI_PLAN_MAGIC */
+       bool            saved;                  /* saved or unsaved plan? */
+       List       *plancache_list;     /* one CachedPlanSource per parsetree */
+       MemoryContext plancxt;          /* Context containing _SPI_plan and data */
+       int                     nargs;                  /* number of plan arguments */
+       Oid                *argtypes;           /* Argument types (NULL if nargs is 0) */
 } _SPI_plan;
 
-
-#define _SPI_CPLAN_CURCXT      0
-#define _SPI_CPLAN_PROCXT      1
-#define _SPI_CPLAN_TOPCXT      2
-
 #endif   /* SPI_PRIV_H */
index 833ec473b134253126336f731818ac4e20dc6f01..4f03cd9e0a2c5fa36f963432487664499d330739 100644 (file)
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/utils/plancache.h,v 1.1 2007/03/13 00:33:43 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/utils/plancache.h,v 1.2 2007/03/15 23:12:07 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -101,5 +101,6 @@ extern void DropCachedPlan(CachedPlanSource *plansource);
 extern CachedPlan *RevalidateCachedPlan(CachedPlanSource *plansource,
                                                                                bool useResOwner);
 extern void ReleaseCachedPlan(CachedPlan *plan, bool useResOwner);
+extern TupleDesc PlanCacheComputeResultDesc(List *stmt_list);
 
 #endif   /* PLANCACHE_H */
index 68a68a6634cdfea1a3558057245ec4378adda010..eb29d7333a8299fb4869554ea1efe9b2907c32d7 100644 (file)
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/pl/plpgsql/src/pl_exec.c,v 1.189 2007/02/20 17:32:18 tgl Exp $
+ *       $PostgreSQL: pgsql/src/pl/plpgsql/src/pl_exec.c,v 1.190 2007/03/15 23:12:07 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -123,8 +123,9 @@ static void exec_prepare_plan(PLpgSQL_execstate *estate,
                                  PLpgSQL_expr *expr);
 static bool exec_simple_check_node(Node *node);
 static void exec_simple_check_plan(PLpgSQL_expr *expr);
-static Datum exec_eval_simple_expr(PLpgSQL_execstate *estate,
+static bool exec_eval_simple_expr(PLpgSQL_execstate *estate,
                                          PLpgSQL_expr *expr,
+                                         Datum *result,
                                          bool *isNull,
                                          Oid *rettype);
 
@@ -409,7 +410,7 @@ plpgsql_exec_function(PLpgSQL_function *func, FunctionCallInfo fcinfo)
                                void       *tmp;
 
                                len = datumGetSize(estate.retval, false, func->fn_rettyplen);
-                               tmp = (void *) SPI_palloc(len);
+                               tmp = SPI_palloc(len);
                                memcpy(tmp, DatumGetPointer(estate.retval), len);
                                estate.retval = PointerGetDatum(tmp);
                        }
@@ -2294,8 +2295,7 @@ exec_prepare_plan(PLpgSQL_execstate *estate,
                                  PLpgSQL_expr *expr)
 {
        int                     i;
-       _SPI_plan  *spi_plan;
-       void       *plan;
+       SPIPlanPtr      plan;
        Oid                *argtypes;
 
        /*
@@ -2343,12 +2343,11 @@ exec_prepare_plan(PLpgSQL_execstate *estate,
                }
        }
        expr->plan = SPI_saveplan(plan);
-       spi_plan = (_SPI_plan *) expr->plan;
-       expr->plan_argtypes = spi_plan->argtypes;
-       expr->expr_simple_expr = NULL;
+       SPI_freeplan(plan);
+       plan = expr->plan;
+       expr->plan_argtypes = plan->argtypes;
        exec_simple_check_plan(expr);
 
-       SPI_freeplan(plan);
        pfree(argtypes);
 }
 
@@ -2374,17 +2373,16 @@ exec_stmt_execsql(PLpgSQL_execstate *estate,
         */
        if (expr->plan == NULL)
        {
-               _SPI_plan  *spi_plan;
                ListCell   *l;
 
                exec_prepare_plan(estate, expr);
                stmt->mod_stmt = false;
-               spi_plan = (_SPI_plan *) expr->plan;
-               foreach(l, spi_plan->stmt_list_list)
+               foreach(l, expr->plan->plancache_list)
                {
+                       CachedPlanSource *plansource = (CachedPlanSource *) lfirst(l);
                        ListCell   *l2;
 
-                       foreach(l2, (List *) lfirst(l))
+                       foreach(l2, plansource->plan->stmt_list)
                        {
                                PlannedStmt *p = (PlannedStmt *) lfirst(l2);
 
@@ -2735,7 +2733,7 @@ exec_stmt_dynfors(PLpgSQL_execstate *estate, PLpgSQL_stmt_dynfors *stmt)
        PLpgSQL_row *row = NULL;
        SPITupleTable *tuptab;
        int                     n;
-       void       *plan;
+       SPIPlanPtr      plan;
        Portal          portal;
        bool            found = false;
 
@@ -2959,7 +2957,7 @@ exec_stmt_open(PLpgSQL_execstate *estate, PLpgSQL_stmt_open *stmt)
                Datum           queryD;
                Oid                     restype;
                char       *querystr;
-               void       *curplan;
+               SPIPlanPtr      curplan;
 
                /* ----------
                 * We evaluate the string expression after the
@@ -3860,10 +3858,11 @@ exec_eval_expr(PLpgSQL_execstate *estate,
                           bool *isNull,
                           Oid *rettype)
 {
+       Datum           result;
        int                     rc;
 
        /*
-        * If not already done create a plan for this expression
+        * If first time through, create a plan for this expression.
         */
        if (expr->plan == NULL)
                exec_prepare_plan(estate, expr);
@@ -3872,9 +3871,12 @@ exec_eval_expr(PLpgSQL_execstate *estate,
         * If this is a simple expression, bypass SPI and use the executor
         * directly
         */
-       if (expr->expr_simple_expr != NULL)
-               return exec_eval_simple_expr(estate, expr, isNull, rettype);
+       if (exec_eval_simple_expr(estate, expr, &result, isNull, rettype))
+               return result;
 
+       /*
+        * Else do it the hard way via exec_run_select
+        */
        rc = exec_run_select(estate, expr, 2, NULL);
        if (rc != SPI_OK_SELECT)
                ereport(ERROR,
@@ -3994,23 +3996,64 @@ exec_run_select(PLpgSQL_execstate *estate,
  * exec_eval_simple_expr -             Evaluate a simple expression returning
  *                                                             a Datum by directly calling ExecEvalExpr().
  *
+ * If successful, store results into *result, *isNull, *rettype and return
+ * TRUE.  If the expression is not simple (any more), return FALSE.
+ *
+ * It is possible though unlikely for a simple expression to become non-simple
+ * (consider for example redefining a trivial view).  We must handle that for
+ * correctness; fortunately it's normally inexpensive to do
+ * RevalidateCachedPlan on a simple expression.  We do not consider the other
+ * direction (non-simple expression becoming simple) because we'll still give
+ * correct results if that happens, and it's unlikely to be worth the cycles
+ * to check.
+ *
  * Note: if pass-by-reference, the result is in the eval_econtext's
  * temporary memory context.  It will be freed when exec_eval_cleanup
  * is done.
  * ----------
  */
-static Datum
+static bool
 exec_eval_simple_expr(PLpgSQL_execstate *estate,
                                          PLpgSQL_expr *expr,
+                                         Datum *result,
                                          bool *isNull,
                                          Oid *rettype)
 {
-       Datum           retval;
        ExprContext *econtext = estate->eval_econtext;
+       CachedPlanSource *plansource;
+       CachedPlan *cplan;
        ParamListInfo paramLI;
        int                     i;
        Snapshot        saveActiveSnapshot;
 
+       /*
+        * Forget it if expression wasn't simple before.
+        */
+       if (expr->expr_simple_expr == NULL)
+               return false;
+
+       /*
+        * Revalidate cached plan, so that we will notice if it became stale.
+        * (We also need to hold a refcount while using the plan.)  Note that
+        * even if replanning occurs, the length of plancache_list can't change,
+        * since it is a property of the raw parsetree generated from the query
+        * text.
+        */
+       Assert(list_length(expr->plan->plancache_list) == 1);
+       plansource = (CachedPlanSource *) linitial(expr->plan->plancache_list);
+       cplan = RevalidateCachedPlan(plansource, true);
+       if (cplan->generation != expr->expr_simple_generation)
+       {
+               /* It got replanned ... is it still simple? */
+               exec_simple_check_plan(expr);
+               if (expr->expr_simple_expr == NULL)
+               {
+                       /* Ooops, release refcount and fail */
+                       ReleaseCachedPlan(cplan, true);
+                       return false;
+               }
+       }
+
        /*
         * Pass back previously-determined result type.
         */
@@ -4018,7 +4061,8 @@ exec_eval_simple_expr(PLpgSQL_execstate *estate,
 
        /*
         * Prepare the expression for execution, if it's not been done already in
-        * the current eval_estate.
+        * the current eval_estate.  (This will be forced to happen if we called
+        * exec_simple_check_plan above.)
         */
        if (expr->expr_simple_id != estate->eval_estate_simple_id)
        {
@@ -4086,10 +4130,10 @@ exec_eval_simple_expr(PLpgSQL_execstate *estate,
                /*
                 * Finally we can call the executor to evaluate the expression
                 */
-               retval = ExecEvalExpr(expr->expr_simple_state,
-                                                         econtext,
-                                                         isNull,
-                                                         NULL);
+               *result = ExecEvalExpr(expr->expr_simple_state,
+                                                          econtext,
+                                                          isNull,
+                                                          NULL);
                MemoryContextSwitchTo(oldcontext);
        }
        PG_CATCH();
@@ -4103,10 +4147,15 @@ exec_eval_simple_expr(PLpgSQL_execstate *estate,
        ActiveSnapshot = saveActiveSnapshot;
        SPI_pop();
 
+       /*
+        * Now we can release our refcount on the cached plan.
+        */
+       ReleaseCachedPlan(cplan, true);
+
        /*
         * That's it.
         */
-       return retval;
+       return true;
 }
 
 
@@ -4673,25 +4722,31 @@ exec_simple_check_node(Node *node)
 static void
 exec_simple_check_plan(PLpgSQL_expr *expr)
 {
-       _SPI_plan  *spi_plan = (_SPI_plan *) expr->plan;
-       List       *sublist;
+       CachedPlanSource *plansource;
        PlannedStmt *stmt;
        Plan       *plan;
        TargetEntry *tle;
 
+       /*
+        * Initialize to "not simple", and remember the plan generation number
+        * we last checked.  (If the query produces more or less than one parsetree
+        * we just leave expr_simple_generation set to 0.)
+        */
        expr->expr_simple_expr = NULL;
+       expr->expr_simple_generation = 0;
 
        /*
         * 1. We can only evaluate queries that resulted in one single execution
         * plan
         */
-       if (list_length(spi_plan->stmt_list_list) != 1)
+       if (list_length(expr->plan->plancache_list) != 1)
                return;
-       sublist = (List *) linitial(spi_plan->stmt_list_list);
-       if (list_length(sublist) != 1)
+       plansource = (CachedPlanSource *) linitial(expr->plan->plancache_list);
+       expr->expr_simple_generation = plansource->generation;
+       if (list_length(plansource->plan->stmt_list) != 1)
                return;
 
-       stmt = (PlannedStmt *) linitial(sublist);
+       stmt = (PlannedStmt *) linitial(plansource->plan->stmt_list);
 
        /*
         * 2. It must be a RESULT plan --> no scan's required
index 9f29fcd5da51721785e17f571e7433ddb031b82a..0b9b90f9170c1ffd46bec5264754941a81cd691b 100644 (file)
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/pl/plpgsql/src/plpgsql.h,v 1.85 2007/02/09 03:35:34 tgl Exp $
+ *       $PostgreSQL: pgsql/src/pl/plpgsql/src/plpgsql.h,v 1.86 2007/03/15 23:12:07 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -173,11 +173,12 @@ typedef struct PLpgSQL_expr
        int                     dtype;
        int                     exprno;
        char       *query;
-       void       *plan;
+       SPIPlanPtr      plan;
        Oid                *plan_argtypes;
        /* fields for "simple expression" fast-path execution: */
        Expr       *expr_simple_expr;           /* NULL means not a simple expr */
-       Oid                     expr_simple_type;
+       int                     expr_simple_generation; /* plancache generation we checked */
+       Oid                     expr_simple_type;               /* result type Oid, if simple */
 
        /*
         * if expr is simple AND prepared in current eval_estate,
index 4980a9ab68b1f4525f7bee470f6816053f4b965c..cac9cfd257454c22b7095a648e68a78ff76d9a35 100644 (file)
@@ -100,3 +100,64 @@ EXECUTE vprep;
  4567890123456789 |  2283945061728394
 (5 rows)
 
+-- Check basic SPI plan invalidation
+create function cache_test(int) returns int as $$
+declare total int;
+begin
+       create temp table t1(f1 int);
+       insert into t1 values($1);
+       insert into t1 values(11);
+       insert into t1 values(12);
+       insert into t1 values(13);
+       select sum(f1) into total from t1;
+       drop table t1;
+       return total;
+end
+$$ language plpgsql;
+select cache_test(1);
+ cache_test 
+------------
+         37
+(1 row)
+
+select cache_test(2);
+ cache_test 
+------------
+         38
+(1 row)
+
+select cache_test(3);
+ cache_test 
+------------
+         39
+(1 row)
+
+-- Check invalidation of plpgsql "simple expression"
+create temp view v1 as
+  select 2+2 as f1;
+create function cache_test_2() returns int as $$
+begin
+       return f1 from v1;
+end$$ language plpgsql;
+select cache_test_2();
+ cache_test_2 
+--------------
+            4
+(1 row)
+
+create or replace temp view v1 as
+  select 2+2+4 as f1;
+select cache_test_2();
+ cache_test_2 
+--------------
+            8
+(1 row)
+
+create or replace temp view v1 as
+  select 2+2+4+(select max(unique1) from tenk1) as f1;
+select cache_test_2();
+ cache_test_2 
+--------------
+        10007
+(1 row)
+
index 551b157a16915879e029f94a5e3ad52ad9e334ee..8f96382dfd62ada37cb2c76d550a2faa56ff2b74 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * $PostgreSQL: pgsql/src/test/regress/regress.c,v 1.69 2007/02/01 19:10:30 momjian Exp $
+ * $PostgreSQL: pgsql/src/test/regress/regress.c,v 1.70 2007/03/15 23:12:07 tgl Exp $
  */
 
 #include "postgres.h"
@@ -451,7 +451,7 @@ extern Datum set_ttdummy(PG_FUNCTION_ARGS);
 
 #define TTDUMMY_INFINITY       999999
 
-static void *splan = NULL;
+static SPIPlanPtr splan = NULL;
 static bool ttoff = false;
 
 PG_FUNCTION_INFO_V1(ttdummy);
@@ -599,7 +599,7 @@ ttdummy(PG_FUNCTION_ARGS)
        /* if there is no plan ... */
        if (splan == NULL)
        {
-               void       *pplan;
+               SPIPlanPtr      pplan;
                Oid                *ctypes;
                char       *query;
 
index b952efe197267a49245cc3a3d0e81ffddb75a3d3..0b34a62c3bd060408f2c4f92e29aa6e326c63e37 100644 (file)
@@ -51,3 +51,43 @@ EXECUTE vprep;
 CREATE OR REPLACE TEMP VIEW voo AS SELECT q1, q2/2 AS q2 FROM foo;
 
 EXECUTE vprep;
+
+-- Check basic SPI plan invalidation
+
+create function cache_test(int) returns int as $$
+declare total int;
+begin
+       create temp table t1(f1 int);
+       insert into t1 values($1);
+       insert into t1 values(11);
+       insert into t1 values(12);
+       insert into t1 values(13);
+       select sum(f1) into total from t1;
+       drop table t1;
+       return total;
+end
+$$ language plpgsql;
+
+select cache_test(1);
+select cache_test(2);
+select cache_test(3);
+
+-- Check invalidation of plpgsql "simple expression"
+
+create temp view v1 as
+  select 2+2 as f1;
+
+create function cache_test_2() returns int as $$
+begin
+       return f1 from v1;
+end$$ language plpgsql;
+
+select cache_test_2();
+
+create or replace temp view v1 as
+  select 2+2+4 as f1;
+select cache_test_2();
+
+create or replace temp view v1 as
+  select 2+2+4+(select max(unique1) from tenk1) as f1;
+select cache_test_2();