*
* 1999 Jan Wieck
*
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/ri_triggers.c,v 1.1 1999/09/30 14:54:22 wieck Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/ri_triggers.c,v 1.2 1999/10/08 12:00:08 wieck Exp $
*
* ----------
*/
#include "fmgr.h"
#include "access/heapam.h"
-#include "catalog/pg_proc.h"
-#include "catalog/pg_type.h"
+#include "catalog/pg_operator.h"
+#include "catalog/catname.h"
#include "commands/trigger.h"
#include "executor/spi.h"
#include "utils/builtins.h"
+#include "utils/mcxt.h"
#include "utils/syscache.h"
+#include "lib/hasht.h"
+
+
+/* ----------
+ * Local definitions
+ * ----------
+ */
+#define RI_CONSTRAINT_NAME_ARGNO 0
+#define RI_FK_RELNAME_ARGNO 1
+#define RI_PK_RELNAME_ARGNO 2
+#define RI_MATCH_TYPE_ARGNO 3
+#define RI_FIRST_ATTNAME_ARGNO 4
+
+#define RI_MAX_NUMKEYS 16
+#define RI_MAX_ARGUMENTS (RI_FIRST_ATTNAME_ARGNO + (RI_MAX_NUMKEYS * 2))
+#define RI_KEYPAIR_FK_IDX 0
+#define RI_KEYPAIR_PK_IDX 1
+
+#define RI_INIT_QUERYHASHSIZE 128
+#define RI_INIT_OPREQHASHSIZE 128
+
+#define RI_MATCH_TYPE_UNSPECIFIED 0
+#define RI_MATCH_TYPE_FULL 1
+#define RI_MATCH_TYPE_PARTIAL 2
+
+#define RI_KEYS_ALL_NULL 0
+#define RI_KEYS_SOME_NULL 1
+#define RI_KEYS_NONE_NULL 2
+
+
+#define RI_PLAN_TYPE_CHECK_FULL 0
+#define RI_PLAN_TYPE_CASCADE_DEL_FULL 1
+
+
+/* ----------
+ * RI_QueryKey
+ *
+ * The key identifying a prepared SPI plan in our private hashtable
+ * ----------
+ */
+typedef struct RI_QueryKey {
+ int32 constr_type;
+ Oid constr_id;
+ int32 constr_queryno;
+ Oid fk_relid;
+ Oid pk_relid;
+ int32 nkeypairs;
+ int16 keypair[RI_MAX_NUMKEYS][2];
+} RI_QueryKey;
+
+
+/* ----------
+ * RI_QueryHashEntry
+ * ----------
+ */
+typedef struct RI_QueryHashEntry {
+ RI_QueryKey key;
+ void *plan;
+} RI_QueryHashEntry;
+
+
+typedef struct RI_OpreqHashEntry {
+ Oid typeid;
+ Oid oprfnid;
+ FmgrInfo oprfmgrinfo;
+} RI_OpreqHashEntry;
+
+
+
+/* ----------
+ * Local data
+ * ----------
+ */
+static HTAB *ri_query_cache = (HTAB *)NULL;
+static HTAB *ri_opreq_cache = (HTAB *)NULL;
+
+
+/* ----------
+ * Local function prototypes
+ * ----------
+ */
+static int ri_DetermineMatchType(char *str);
+static int ri_NullCheck(Relation rel, HeapTuple tup,
+ RI_QueryKey *key, int pairidx);
+static void ri_BuildQueryKeyFull(RI_QueryKey *key, Oid constr_id,
+ int32 constr_queryno,
+ Relation fk_rel, Relation pk_rel,
+ int argc, char **argv);
+static bool ri_KeysEqual(Relation rel, HeapTuple oldtup, HeapTuple newtup,
+ RI_QueryKey *key, int pairidx);
+static bool ri_AttributesEqual(Oid typeid, Datum oldvalue, Datum newvalue);
+
+static void ri_InitHashTables(void);
+static void *ri_FetchPreparedPlan(RI_QueryKey *key);
+static void ri_HashPreparedPlan(RI_QueryKey *key, void *plan);
+
+
+
+/* ----------
+ * RI_FKey_check -
+ *
+ * Check foreign key existance (combined for INSERT and UPDATE).
+ * ----------
+ */
+static HeapTuple
+RI_FKey_check (FmgrInfo *proinfo)
+{
+ TriggerData *trigdata;
+ int tgnargs;
+ char **tgargs;
+ Relation fk_rel;
+ Relation pk_rel;
+ HeapTuple new_row;
+ HeapTuple old_row;
+ RI_QueryKey qkey;
+ void *qplan;
+ Datum check_values[RI_MAX_NUMKEYS];
+ char check_nulls[RI_MAX_NUMKEYS + 1];
+ bool isnull;
+ int i;
+
+ trigdata = CurrentTriggerData;
+ CurrentTriggerData = NULL;
+
+ /* ----------
+ * Check that this is a valid trigger call on the right time and event.
+ * ----------
+ */
+ if (trigdata == NULL)
+ elog(ERROR, "RI_FKey_check() not fired by trigger manager");
+ if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
+ !TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
+ elog(ERROR, "RI_FKey_check() must be fired AFTER ROW");
+ if (!TRIGGER_FIRED_BY_INSERT(trigdata->tg_event) &&
+ !TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
+ elog(ERROR, "RI_FKey_check() must be fired for INSERT or UPDATE");
+
+ /* ----------
+ * Check for the correct # of call arguments
+ * ----------
+ */
+ tgnargs = trigdata->tg_trigger->tgnargs;
+ tgargs = trigdata->tg_trigger->tgargs;
+ if (tgnargs < 4 || (tgnargs % 2) != 0)
+ elog(ERROR, "wrong # of arguments in call to RI_FKey_check()");
+ if (tgnargs > RI_MAX_ARGUMENTS)
+ elog(ERROR, "too many keys (%d max) in call to RI_FKey_check()",
+ RI_MAX_NUMKEYS);
+
+ /* ----------
+ * Get the relation descriptors of the FK and PK tables and
+ * the new tuple.
+ * ----------
+ */
+ fk_rel = trigdata->tg_relation;
+ pk_rel = heap_openr(tgargs[RI_PK_RELNAME_ARGNO], NoLock);
+ if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
+ {
+ old_row = trigdata->tg_trigtuple;
+ new_row = trigdata->tg_newtuple;
+ } else {
+ old_row = NULL;
+ new_row = trigdata->tg_trigtuple;
+ }
+
+ /* ----------
+ * SQL3 11.9 <referential constraint definition>
+ * Gereral rules 2) a):
+ * If Rf and Rt are empty (no columns to compare given)
+ * constraint is true if 0 < (SELECT COUNT(*) FROM T)
+ * ----------
+ */
+ if (tgnargs == 4) {
+ ri_BuildQueryKeyFull(&qkey, trigdata->tg_trigger->tgoid, 1,
+ fk_rel, pk_rel,
+ tgnargs, tgargs);
+
+ if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
+ {
+ char querystr[8192];
+
+ /* ----------
+ * The query string built is
+ * SELECT oid FROM <pktable>
+ * ----------
+ */
+ sprintf(querystr, "SELECT oid FROM \"%s\"",
+ tgargs[RI_PK_RELNAME_ARGNO]);
+
+ /* ----------
+ * Prepare, save and remember the new plan.
+ * ----------
+ */
+ qplan = SPI_prepare(querystr, 0, NULL);
+ qplan = SPI_saveplan(qplan);
+ ri_HashPreparedPlan(&qkey, qplan);
+ }
+ heap_close(pk_rel, NoLock);
+
+ /* ----------
+ * Execute the plan
+ * ----------
+ */
+ if (SPI_connect() != SPI_OK_CONNECT)
+ elog(NOTICE, "SPI_connect() failed in RI_FKey_check()");
+
+ if (SPI_execp(qplan, check_values, check_nulls, 1) != SPI_OK_SELECT)
+ elog(ERROR, "SPI_execp() failed in RI_FKey_check()");
+
+ if (SPI_processed == 0)
+ elog(ERROR, "%s referential integrity violation - "
+ "no rows found in %s",
+ tgargs[RI_CONSTRAINT_NAME_ARGNO],
+ tgargs[RI_PK_RELNAME_ARGNO]);
+
+ if (SPI_finish() != SPI_OK_FINISH)
+ elog(NOTICE, "SPI_finish() failed in RI_FKey_check()");
+
+ return NULL;
+
+ }
+
+ switch (ri_DetermineMatchType(tgargs[RI_MATCH_TYPE_ARGNO]))
+ {
+ /* ----------
+ * SQL3 11.9 <referential constraint definition>
+ * Gereral rules 2) b):
+ * <match type> is not specified
+ * ----------
+ */
+ case RI_MATCH_TYPE_UNSPECIFIED:
+ elog(ERROR, "MATCH <unspecified> not yet supported");
+ return NULL;
+
+ /* ----------
+ * SQL3 11.9 <referential constraint definition>
+ * Gereral rules 2) c):
+ * MATCH PARTIAL
+ * ----------
+ */
+ case RI_MATCH_TYPE_PARTIAL:
+ elog(ERROR, "MATCH PARTIAL not yet supported");
+ return NULL;
+
+ /* ----------
+ * SQL3 11.9 <referential constraint definition>
+ * Gereral rules 2) d):
+ * MATCH FULL
+ * ----------
+ */
+ case RI_MATCH_TYPE_FULL:
+ ri_BuildQueryKeyFull(&qkey, trigdata->tg_trigger->tgoid, 2,
+ fk_rel, pk_rel,
+ tgnargs, tgargs);
+
+ switch (ri_NullCheck(fk_rel, new_row, &qkey, RI_KEYPAIR_FK_IDX))
+ {
+ case RI_KEYS_ALL_NULL:
+ /* ----------
+ * No check - if NULLs are allowed at all is
+ * already checked by NOT NULL constraint.
+ * ----------
+ */
+ heap_close(pk_rel, NoLock);
+ return NULL;
+
+ case RI_KEYS_SOME_NULL:
+ /* ----------
+ * Not allowed - MATCH FULL says either all or none
+ * of the attributes can be NULLs
+ * ----------
+ */
+ elog(ERROR, "%s referential integrity violation - "
+ "MATCH FULL doesn't allow mixing of NULL "
+ "and NON-NULL key values",
+ tgargs[RI_CONSTRAINT_NAME_ARGNO]);
+ break;
+
+ case RI_KEYS_NONE_NULL:
+ /* ----------
+ * Have a full qualified key - continue below
+ * ----------
+ */
+ break;
+ }
+ heap_close(pk_rel, NoLock);
+
+ /* ----------
+ * If we're called on UPDATE, check if there was a change
+ * in the foreign key at all.
+ * ----------
+ */
+ if (TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
+ {
+ if (ri_KeysEqual(fk_rel, old_row, new_row, &qkey,
+ RI_KEYPAIR_FK_IDX))
+ return NULL;
+ }
+
+ if (SPI_connect() != SPI_OK_CONNECT)
+ elog(NOTICE, "SPI_connect() failed in RI_FKey_check()");
+
+ /* ----------
+ * Fetch or prepare a saved plan for the real check
+ * ----------
+ */
+ if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
+ {
+ char buf[256];
+ char querystr[8192];
+ char *querysep;
+ Oid queryoids[RI_MAX_NUMKEYS];
+
+ /* ----------
+ * The query string built is
+ * SELECT oid FROM <pktable> WHERE pkatt1 = $1 [AND ...]
+ * The type id's for the $ parameters are those of the
+ * corresponding FK attributes. Thus, SPI_prepare could
+ * eventually fail if the parser cannot identify some way
+ * how to compare these two types by '='.
+ * ----------
+ */
+ sprintf(querystr, "SELECT oid FROM \"%s\"",
+ tgargs[RI_PK_RELNAME_ARGNO]);
+ querysep = "WHERE";
+ for (i = 0; i < qkey.nkeypairs; i++)
+ {
+ sprintf(buf, " %s \"%s\" = $%d", querysep,
+ tgargs[5 + i * 2], i + 1);
+ strcat(querystr, buf);
+ querysep = "AND";
+ queryoids[i] = SPI_gettypeid(fk_rel->rd_att,
+ qkey.keypair[i][RI_KEYPAIR_FK_IDX]);
+ }
+
+ /* ----------
+ * Prepare, save and remember the new plan.
+ * ----------
+ */
+ qplan = SPI_prepare(querystr, qkey.nkeypairs, queryoids);
+ qplan = SPI_saveplan(qplan);
+ ri_HashPreparedPlan(&qkey, qplan);
+ }
+
+ /* ----------
+ * We have a plan now. Build up the arguments for SPI_execp()
+ * from the key values in the new FK tuple.
+ * ----------
+ */
+ for (i = 0; i < qkey.nkeypairs; i++)
+ {
+ check_values[i] = SPI_getbinval(new_row,
+ fk_rel->rd_att,
+ qkey.keypair[i][RI_KEYPAIR_FK_IDX],
+ &isnull);
+ if (isnull)
+ check_nulls[i] = 'n';
+ else
+ check_nulls[i] = ' ';
+ }
+ check_nulls[RI_MAX_NUMKEYS] = '\0';
+
+ /* ----------
+ * Now check that foreign key exists in PK table
+ * ----------
+ */
+ if (SPI_execp(qplan, check_values, check_nulls, 1) != SPI_OK_SELECT)
+ elog(ERROR, "SPI_execp() failed in RI_FKey_check()");
+
+ if (SPI_processed == 0)
+ elog(ERROR, "%s referential integrity violation - "
+ "key referenced from %s not found in %s",
+ tgargs[RI_CONSTRAINT_NAME_ARGNO],
+ tgargs[RI_FK_RELNAME_ARGNO],
+ tgargs[RI_PK_RELNAME_ARGNO]);
+
+ if (SPI_finish() != SPI_OK_FINISH)
+ elog(NOTICE, "SPI_finish() failed in RI_FKey_check()");
+
+ return NULL;
+ }
+
+ /* ----------
+ * Never reached
+ * ----------
+ */
+ elog(ERROR, "internal error #1 in ri_triggers.c");
+ return NULL;
+}
+
/* ----------
* RI_FKey_check_ins -
HeapTuple
RI_FKey_check_ins (FmgrInfo *proinfo)
{
- CurrentTriggerData = NULL;
-
- elog(NOTICE, "RI_FKey_check_ins() called\n");
- return NULL;
+ return RI_FKey_check(proinfo);
}
HeapTuple
RI_FKey_check_upd (FmgrInfo *proinfo)
{
- CurrentTriggerData = NULL;
-
- elog(NOTICE, "RI_FKey_check_upd() called\n");
- return NULL;
+ return RI_FKey_check(proinfo);
}
HeapTuple
RI_FKey_cascade_del (FmgrInfo *proinfo)
{
+ TriggerData *trigdata;
+ int tgnargs;
+ char **tgargs;
+ Relation fk_rel;
+ Relation pk_rel;
+ HeapTuple old_row;
+ RI_QueryKey qkey;
+ void *qplan;
+ Datum del_values[RI_MAX_NUMKEYS];
+ char del_nulls[RI_MAX_NUMKEYS + 1];
+ bool isnull;
+ int i;
+
+ trigdata = CurrentTriggerData;
CurrentTriggerData = NULL;
- elog(NOTICE, "RI_FKey_cascade_del() called\n");
+ /* ----------
+ * Check that this is a valid trigger call on the right time and event.
+ * ----------
+ */
+ if (trigdata == NULL)
+ elog(ERROR, "RI_FKey_cascade_del() not fired by trigger manager");
+ if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
+ !TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
+ elog(ERROR, "RI_FKey_cascade_del() must be fired AFTER ROW");
+ if (!TRIGGER_FIRED_BY_DELETE(trigdata->tg_event))
+ elog(ERROR, "RI_FKey_cascade_del() must be fired for DELETE");
+
+ /* ----------
+ * Check for the correct # of call arguments
+ * ----------
+ */
+ tgnargs = trigdata->tg_trigger->tgnargs;
+ tgargs = trigdata->tg_trigger->tgargs;
+ if (tgnargs < 4 || (tgnargs % 2) != 0)
+ elog(ERROR, "wrong # of arguments in call to RI_FKey_cascade_del()");
+ if (tgnargs > RI_MAX_ARGUMENTS)
+ elog(ERROR, "too many keys (%d max) in call to RI_FKey_cascade_del()",
+ RI_MAX_NUMKEYS);
+
+ /* ----------
+ * Nothing to do if no column names to compare given
+ * ----------
+ */
+ if (tgnargs == 4)
+ return NULL;
+
+ /* ----------
+ * Get the relation descriptors of the FK and PK tables and
+ * the old tuple.
+ * ----------
+ */
+ fk_rel = heap_openr(tgargs[RI_FK_RELNAME_ARGNO], NoLock);
+ pk_rel = trigdata->tg_relation;
+ old_row = trigdata->tg_trigtuple;
+
+ switch (ri_DetermineMatchType(tgargs[RI_MATCH_TYPE_ARGNO]))
+ {
+ /* ----------
+ * SQL3 11.9 <referential constraint definition>
+ * Gereral rules 6) a) i):
+ * MATCH <unspecified> or MATCH FULL
+ * ... ON DELETE CASCADE
+ * ----------
+ */
+ case RI_MATCH_TYPE_UNSPECIFIED:
+ case RI_MATCH_TYPE_FULL:
+ ri_BuildQueryKeyFull(&qkey, trigdata->tg_trigger->tgoid, 1,
+ fk_rel, pk_rel,
+ tgnargs, tgargs);
+
+ switch (ri_NullCheck(pk_rel, old_row, &qkey, RI_KEYPAIR_PK_IDX))
+ {
+ case RI_KEYS_ALL_NULL:
+ case RI_KEYS_SOME_NULL:
+ /* ----------
+ * No check - MATCH FULL means there cannot be any
+ * reference to old key if it contains NULL
+ * ----------
+ */
+ heap_close(fk_rel, NoLock);
+ return NULL;
+
+ case RI_KEYS_NONE_NULL:
+ /* ----------
+ * Have a full qualified key - continue below
+ * ----------
+ */
+ break;
+ }
+ heap_close(fk_rel, NoLock);
+
+ if (SPI_connect() != SPI_OK_CONNECT)
+ elog(NOTICE, "SPI_connect() failed in RI_FKey_check()");
+
+ /* ----------
+ * Fetch or prepare a saved plan for the cascaded delete
+ * ----------
+ */
+ if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
+ {
+ char buf[256];
+ char querystr[8192];
+ char *querysep;
+ Oid queryoids[RI_MAX_NUMKEYS];
+
+ /* ----------
+ * The query string built is
+ * DELETE FROM <fktable> WHERE fkatt1 = $1 [AND ...]
+ * The type id's for the $ parameters are those of the
+ * corresponding PK attributes. Thus, SPI_prepare could
+ * eventually fail if the parser cannot identify some way
+ * how to compare these two types by '='.
+ * ----------
+ */
+ sprintf(querystr, "DELETE FROM \"%s\"",
+ tgargs[RI_FK_RELNAME_ARGNO]);
+ querysep = "WHERE";
+ for (i = 0; i < qkey.nkeypairs; i++)
+ {
+ sprintf(buf, " %s \"%s\" = $%d", querysep,
+ tgargs[4 + i * 2], i + 1);
+ strcat(querystr, buf);
+ querysep = "AND";
+ queryoids[i] = SPI_gettypeid(pk_rel->rd_att,
+ qkey.keypair[i][RI_KEYPAIR_PK_IDX]);
+ }
+
+ /* ----------
+ * Prepare, save and remember the new plan.
+ * ----------
+ */
+ qplan = SPI_prepare(querystr, qkey.nkeypairs, queryoids);
+ qplan = SPI_saveplan(qplan);
+ ri_HashPreparedPlan(&qkey, qplan);
+ }
+
+ /* ----------
+ * We have a plan now. Build up the arguments for SPI_execp()
+ * from the key values in the deleted PK tuple.
+ * ----------
+ */
+ for (i = 0; i < qkey.nkeypairs; i++)
+ {
+ del_values[i] = SPI_getbinval(old_row,
+ pk_rel->rd_att,
+ qkey.keypair[i][RI_KEYPAIR_PK_IDX],
+ &isnull);
+ if (isnull)
+ del_nulls[i] = 'n';
+ else
+ del_nulls[i] = ' ';
+ }
+ del_nulls[RI_MAX_NUMKEYS] = '\0';
+
+ /* ----------
+ * Now delete constraint
+ * ----------
+ */
+ if (SPI_execp(qplan, del_values, del_nulls, 1) != SPI_OK_DELETE)
+ elog(ERROR, "SPI_execp() failed in RI_FKey_cascade_del()");
+
+ if (SPI_finish() != SPI_OK_FINISH)
+ elog(NOTICE, "SPI_finish() failed in RI_FKey_cascade_del()");
+
+ return NULL;
+
+ /* ----------
+ * Handle MATCH PARTIAL cascaded delete.
+ * ----------
+ */
+ case RI_MATCH_TYPE_PARTIAL:
+ elog(ERROR, "MATCH PARTIAL not yet supported");
+ return NULL;
+ }
+
+ /* ----------
+ * Never reached
+ * ----------
+ */
+ elog(ERROR, "internal error #2 in ri_triggers.c");
return NULL;
}
HeapTuple
RI_FKey_cascade_upd (FmgrInfo *proinfo)
{
+ TriggerData *trigdata;
+
+ trigdata = CurrentTriggerData;
CurrentTriggerData = NULL;
elog(NOTICE, "RI_FKey_cascade_upd() called\n");
HeapTuple
RI_FKey_restrict_del (FmgrInfo *proinfo)
{
+ TriggerData *trigdata;
+
+ trigdata = CurrentTriggerData;
CurrentTriggerData = NULL;
elog(NOTICE, "RI_FKey_restrict_del() called\n");
HeapTuple
RI_FKey_restrict_upd (FmgrInfo *proinfo)
{
+ TriggerData *trigdata;
+
+ trigdata = CurrentTriggerData;
CurrentTriggerData = NULL;
elog(NOTICE, "RI_FKey_restrict_upd() called\n");
HeapTuple
RI_FKey_setnull_del (FmgrInfo *proinfo)
{
+ TriggerData *trigdata;
+
+ trigdata = CurrentTriggerData;
CurrentTriggerData = NULL;
elog(NOTICE, "RI_FKey_setnull_del() called\n");
HeapTuple
RI_FKey_setnull_upd (FmgrInfo *proinfo)
{
+ TriggerData *trigdata;
+
+ trigdata = CurrentTriggerData;
CurrentTriggerData = NULL;
elog(NOTICE, "RI_FKey_setnull_upd() called\n");
HeapTuple
RI_FKey_setdefault_del (FmgrInfo *proinfo)
{
+ TriggerData *trigdata;
+
+ trigdata = CurrentTriggerData;
CurrentTriggerData = NULL;
elog(NOTICE, "RI_FKey_setdefault_del() called\n");
HeapTuple
RI_FKey_setdefault_upd (FmgrInfo *proinfo)
{
+ TriggerData *trigdata;
+
+ trigdata = CurrentTriggerData;
CurrentTriggerData = NULL;
elog(NOTICE, "RI_FKey_setdefault_upd() called\n");
}
+
+
+
+/* ----------
+ * Local functions below
+ * ----------
+ */
+
+
+
+
+
+/* ----------
+ * ri_DetermineMatchType -
+ *
+ * Convert the MATCH TYPE string into a switchable int
+ * ----------
+ */
+static int
+ri_DetermineMatchType(char *str)
+{
+ if (!strcmp(str, "UNSPECIFIED"))
+ return RI_MATCH_TYPE_UNSPECIFIED;
+ if (!strcmp(str, "FULL"))
+ return RI_MATCH_TYPE_FULL;
+ if (!strcmp(str, "PARTIAL"))
+ return RI_MATCH_TYPE_PARTIAL;
+
+ elog(ERROR, "unrecognized referential integrity MATCH type '%s'", str);
+ return 0;
+}
+
+
+/* ----------
+ * ri_BuildQueryKeyFull -
+ *
+ * Build up a new hashtable key for a prepared SPI plan of a
+ * constraint trigger of MATCH FULL. The key consists of:
+ *
+ * constr_type is FULL
+ * constr_id is the OID of the pg_trigger row that invoked us
+ * constr_queryno is an internal number of the query inside the proc
+ * fk_relid is the OID of referencing relation
+ * pk_relid is the OID of referenced relation
+ * nkeypairs is the number of keypairs
+ * following are the attribute number keypairs of the trigger invocation
+ *
+ * At least for MATCH FULL this builds a unique key per plan.
+ * ----------
+ */
+static void
+ri_BuildQueryKeyFull(RI_QueryKey *key, Oid constr_id, int32 constr_queryno,
+ Relation fk_rel, Relation pk_rel,
+ int argc, char **argv)
+{
+ int i;
+ int j;
+ int fno;
+
+ /* ----------
+ * Initialize the key and fill in type, oid's and number of keypairs
+ * ----------
+ */
+ memset ((void *)key, 0, sizeof(RI_QueryKey));
+ key->constr_type = RI_MATCH_TYPE_FULL;
+ key->constr_id = constr_id;
+ key->constr_queryno = constr_queryno;
+ key->fk_relid = fk_rel->rd_id;
+ key->pk_relid = pk_rel->rd_id;
+ key->nkeypairs = (argc - RI_FIRST_ATTNAME_ARGNO) / 2;
+
+ /* ----------
+ * Lookup the attribute numbers of the arguments to the trigger call
+ * and fill in the keypairs.
+ * ----------
+ */
+ for (i = 0, j = RI_FIRST_ATTNAME_ARGNO; j < argc; i++, j += 2)
+ {
+ fno = SPI_fnumber(fk_rel->rd_att, argv[j]);
+ if (fno == SPI_ERROR_NOATTRIBUTE)
+ elog(ERROR, "constraint %s: table %s does not have an attribute %s",
+ argv[RI_CONSTRAINT_NAME_ARGNO],
+ argv[RI_FK_RELNAME_ARGNO],
+ argv[j]);
+ key->keypair[i][RI_KEYPAIR_FK_IDX] = fno;
+
+ fno = SPI_fnumber(pk_rel->rd_att, argv[j + 1]);
+ if (fno == SPI_ERROR_NOATTRIBUTE)
+ elog(ERROR, "constraint %s: table %s does not have an attribute %s",
+ argv[RI_CONSTRAINT_NAME_ARGNO],
+ argv[RI_PK_RELNAME_ARGNO],
+ argv[j + 1]);
+ key->keypair[i][RI_KEYPAIR_PK_IDX] = fno;
+ }
+
+ return;
+}
+
+
+/* ----------
+ * ri_NullCheck -
+ *
+ * Determine the NULL state of all key values in a tuple
+ *
+ * Returns one of RI_KEYS_ALL_NULL, RI_KEYS_NONE_NULL or RI_KEYS_SOME_NULL.
+ * ----------
+ */
+static int
+ri_NullCheck(Relation rel, HeapTuple tup, RI_QueryKey *key, int pairidx)
+{
+ int i;
+ bool isnull;
+ bool allnull = true;
+ bool nonenull = true;
+
+ for (i = 0; i < key->nkeypairs; i++)
+ {
+ isnull = false;
+ SPI_getbinval(tup, rel->rd_att, key->keypair[i][pairidx], &isnull);
+ if (isnull)
+ nonenull = false;
+ else
+ allnull = false;
+ }
+
+ if (allnull)
+ return RI_KEYS_ALL_NULL;
+
+ if (nonenull)
+ return RI_KEYS_NONE_NULL;
+
+ return RI_KEYS_SOME_NULL;
+}
+
+
+/* ----------
+ * ri_InitHashTables -
+ *
+ * Initialize our internal hash tables for prepared
+ * query plans and equal operators.
+ * ----------
+ */
+static void
+ri_InitHashTables(void)
+{
+ HASHCTL ctl;
+
+ memset(&ctl, 0, sizeof(ctl));
+ ctl.keysize = sizeof(RI_QueryKey);
+ ctl.datasize = sizeof(void *);
+ ri_query_cache = hash_create(RI_INIT_QUERYHASHSIZE, &ctl, HASH_ELEM);
+
+ memset(&ctl, 0, sizeof(ctl));
+ ctl.keysize = sizeof(Oid);
+ ctl.datasize = sizeof(Oid) + sizeof(FmgrInfo);
+ ctl.hash = tag_hash;
+ ri_opreq_cache = hash_create(RI_INIT_OPREQHASHSIZE, &ctl,
+ HASH_ELEM | HASH_FUNCTION);
+}
+
+
+/* ----------
+ * ri_FetchPreparedPlan -
+ *
+ * Lookup for a query key in our private hash table of prepared
+ * and saved SPI execution plans. Return the plan if found or NULL.
+ * ----------
+ */
+static void *
+ri_FetchPreparedPlan(RI_QueryKey *key)
+{
+ RI_QueryHashEntry *entry;
+ bool found;
+
+ /* ----------
+ * On the first call initialize the hashtable
+ * ----------
+ */
+ if (!ri_query_cache)
+ ri_InitHashTables();
+
+ /* ----------
+ * Lookup for the key
+ * ----------
+ */
+ entry = (RI_QueryHashEntry *)hash_search(ri_query_cache,
+ (char *)key, HASH_FIND, &found);
+ if (entry == NULL)
+ elog(FATAL, "error in RI plan cache");
+ if (!found)
+ return NULL;
+ return entry->plan;
+}
+
+
+/* ----------
+ * ri_HashPreparedPlan -
+ *
+ * Add another plan to our private SPI query plan hashtable.
+ * ----------
+ */
+static void
+ri_HashPreparedPlan(RI_QueryKey *key, void *plan)
+{
+ RI_QueryHashEntry *entry;
+ bool found;
+
+ /* ----------
+ * On the first call initialize the hashtable
+ * ----------
+ */
+ if (!ri_query_cache)
+ ri_InitHashTables();
+
+ /* ----------
+ * Add the new plan.
+ * ----------
+ */
+ entry = (RI_QueryHashEntry *)hash_search(ri_query_cache,
+ (char *)key, HASH_ENTER, &found);
+ if (entry == NULL)
+ elog(FATAL, "can't insert into RI plan cache");
+ entry->plan = plan;
+}
+
+
+/* ----------
+ * ri_KeysEqual -
+ *
+ * Check if all key values in OLD and NEW are equal.
+ * ----------
+ */
+static bool
+ri_KeysEqual(Relation rel, HeapTuple oldtup, HeapTuple newtup,
+ RI_QueryKey *key, int pairidx)
+{
+ int i;
+ Oid typeid;
+ Datum oldvalue;
+ Datum newvalue;
+ bool isnull;
+
+ for (i = 0; i < key->nkeypairs; i++)
+ {
+ /* ----------
+ * Get one attributes oldvalue. If it is NULL - they're not equal.
+ * ----------
+ */
+ oldvalue = SPI_getbinval(oldtup, rel->rd_att,
+ key->keypair[i][pairidx], &isnull);
+ if (isnull)
+ return false;
+
+ /* ----------
+ * Get one attributes oldvalue. If it is NULL - they're not equal.
+ * ----------
+ */
+ newvalue = SPI_getbinval(newtup, rel->rd_att,
+ key->keypair[i][pairidx], &isnull);
+ if (isnull)
+ return false;
+
+ /* ----------
+ * Get the attributes type OID and call the '=' operator
+ * to compare the values.
+ * ----------
+ */
+ typeid = SPI_gettypeid(rel->rd_att, key->keypair[i][pairidx]);
+ if (!ri_AttributesEqual(typeid, oldvalue, newvalue))
+ return false;
+ }
+
+ return true;
+}
+
+
+/* ----------
+ * ri_AttributesEqual -
+ *
+ * Call the type specific '=' operator comparision function
+ * for two values.
+ * ----------
+ */
+static bool
+ri_AttributesEqual(Oid typeid, Datum oldvalue, Datum newvalue)
+{
+ RI_OpreqHashEntry *entry;
+ bool found;
+ Datum result;
+
+ /* ----------
+ * On the first call initialize the hashtable
+ * ----------
+ */
+ if (!ri_query_cache)
+ ri_InitHashTables();
+
+ /* ----------
+ * Try to find the '=' operator for this type in our cache
+ * ----------
+ */
+ entry = (RI_OpreqHashEntry *)hash_search(ri_opreq_cache,
+ (char *)&typeid, HASH_FIND, &found);
+ if (entry == NULL)
+ elog(FATAL, "error in RI operator cache");
+
+ /* ----------
+ * If not found, lookup the OPRNAME system cache for it
+ * and remember that info.
+ * ----------
+ */
+ if (!found)
+ {
+ HeapTuple opr_tup;
+ Form_pg_operator opr_struct;
+
+ opr_tup = SearchSysCacheTuple(OPRNAME,
+ PointerGetDatum("="),
+ ObjectIdGetDatum(typeid),
+ ObjectIdGetDatum(typeid),
+ CharGetDatum('b'));
+
+ if (!HeapTupleIsValid(opr_tup))
+ elog(ERROR, "ri_AttributesEqual(): cannot find '=' operator "
+ "for type %d", typeid);
+ opr_struct = (Form_pg_operator) GETSTRUCT(opr_tup);
+
+ entry = (RI_OpreqHashEntry *)hash_search(ri_opreq_cache,
+ (char *)&typeid, HASH_ENTER, &found);
+ if (entry == NULL)
+ elog(FATAL, "can't insert into RI operator cache");
+
+ entry->oprfnid = opr_struct->oprcode;
+ memset(&(entry->oprfmgrinfo), 0, sizeof(FmgrInfo));
+ }
+
+ /* ----------
+ * Call the type specific '=' function
+ * ----------
+ */
+ fmgr_info(entry->oprfnid, &(entry->oprfmgrinfo));
+ result = (Datum)(*fmgr_faddr(&(entry->oprfmgrinfo)))(oldvalue, newvalue);
+ return (bool)result;
+}
+
+
projects / postgresql / commitdiff