*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/executor/functions.c,v 1.136 2009/11/04 22:26:05 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/executor/functions.c,v 1.137 2009/12/14 02:15:51 tgl Exp $
*
*-------------------------------------------------------------------------
*/
fcache->returnsTuple = check_sql_fn_retval(foid,
rettype,
queryTree_list,
- false,
+ NULL,
&fcache->junkFilter);
if (fcache->returnsTuple)
* function definition of a polymorphic function.)
*
* This function returns true if the sql function returns the entire tuple
- * result of its final statement, and false otherwise. Note that because we
- * allow "SELECT rowtype_expression", this may be false even when the declared
- * function return type is a rowtype.
+ * result of its final statement, or false if it returns just the first column
+ * result of that statement. It throws an error if the final statement doesn't
+ * return the right type at all.
*
- * If insertRelabels is true, then binary-compatible cases are dealt with
- * by actually inserting RelabelType nodes into the output targetlist;
- * obviously the caller must pass a parsetree that it's okay to modify in this
- * case.
+ * Note that because we allow "SELECT rowtype_expression", the result can be
+ * false even when the declared function return type is a rowtype.
+ *
+ * If modifyTargetList isn't NULL, the function will modify the final
+ * statement's targetlist in two cases:
+ * (1) if the tlist returns values that are binary-coercible to the expected
+ * type rather than being exactly the expected type. RelabelType nodes will
+ * be inserted to make the result types match exactly.
+ * (2) if there are dropped columns in the declared result rowtype. NULL
+ * output columns will be inserted in the tlist to match them.
+ * (Obviously the caller must pass a parsetree that is okay to modify when
+ * using this flag.) Note that this flag does not affect whether the tlist is
+ * considered to be a legal match to the result type, only how we react to
+ * allowed not-exact-match cases. *modifyTargetList will be set true iff
+ * we had to make any "dangerous" changes that could modify the semantics of
+ * the statement. If it is set true, the caller should not use the modified
+ * statement, but for simplicity we apply the changes anyway.
*
* If junkFilter isn't NULL, then *junkFilter is set to a JunkFilter defined
* to convert the function's tuple result to the correct output tuple type.
*/
bool
check_sql_fn_retval(Oid func_id, Oid rettype, List *queryTreeList,
- bool insertRelabels,
+ bool *modifyTargetList,
JunkFilter **junkFilter)
{
Query *parse;
+ List **tlist_ptr;
List *tlist;
int tlistlen;
char fn_typtype;
AssertArg(!IsPolymorphicType(rettype));
+ if (modifyTargetList)
+ *modifyTargetList = false; /* initialize for no change */
if (junkFilter)
*junkFilter = NULL; /* initialize in case of VOID result */
parse->utilityStmt == NULL &&
parse->intoClause == NULL)
{
+ tlist_ptr = &parse->targetList;
tlist = parse->targetList;
}
else if (parse &&
parse->commandType == CMD_DELETE) &&
parse->returningList)
{
+ tlist_ptr = &parse->returningList;
tlist = parse->returningList;
}
else
format_type_be(rettype)),
errdetail("Actual return type is %s.",
format_type_be(restype))));
- if (insertRelabels && restype != rettype)
+ if (modifyTargetList && restype != rettype)
+ {
tle->expr = (Expr *) makeRelabelType(tle->expr,
rettype,
-1,
COERCE_DONTCARE);
+ /* Relabel is dangerous if TLE is a sort/group or setop column */
+ if (tle->ressortgroupref != 0 || parse->setOperations)
+ *modifyTargetList = true;
+ }
/* Set up junk filter if needed */
if (junkFilter)
int tupnatts; /* physical number of columns in tuple */
int tuplogcols; /* # of nondeleted columns in tuple */
int colindex; /* physical column index */
+ List *newtlist; /* new non-junk tlist entries */
+ List *junkattrs; /* new junk tlist entries */
/*
* If the target list is of length 1, and the type of the varnode in
restype = exprType((Node *) tle->expr);
if (IsBinaryCoercible(restype, rettype))
{
- if (insertRelabels && restype != rettype)
+ if (modifyTargetList && restype != rettype)
+ {
tle->expr = (Expr *) makeRelabelType(tle->expr,
rettype,
-1,
COERCE_DONTCARE);
+ /* Relabel is dangerous if sort/group or setop column */
+ if (tle->ressortgroupref != 0 || parse->setOperations)
+ *modifyTargetList = true;
+ }
/* Set up junk filter if needed */
if (junkFilter)
*junkFilter = ExecInitJunkFilter(tlist, false, NULL);
/*
* Verify that the targetlist matches the return tuple type. We scan
* the non-deleted attributes to ensure that they match the datatypes
- * of the non-resjunk columns.
+ * of the non-resjunk columns. For deleted attributes, insert NULL
+ * result columns if the caller asked for that.
*/
tupnatts = tupdesc->natts;
tuplogcols = 0; /* we'll count nondeleted cols as we go */
colindex = 0;
+ newtlist = NIL; /* these are only used if modifyTargetList */
+ junkattrs = NIL;
foreach(lc, tlist)
{
Oid atttype;
if (tle->resjunk)
+ {
+ if (modifyTargetList)
+ junkattrs = lappend(junkattrs, tle);
continue;
+ }
do
{
format_type_be(rettype)),
errdetail("Final statement returns too many columns.")));
attr = tupdesc->attrs[colindex - 1];
+ if (attr->attisdropped && modifyTargetList)
+ {
+ Expr *null_expr;
+
+ /* The type of the null we insert isn't important */
+ null_expr = (Expr *) makeConst(INT4OID,
+ -1,
+ sizeof(int32),
+ (Datum) 0,
+ true, /* isnull */
+ true /* byval */ );
+ newtlist = lappend(newtlist,
+ makeTargetEntry(null_expr,
+ colindex,
+ NULL,
+ false));
+ /* NULL insertion is dangerous in a setop */
+ if (parse->setOperations)
+ *modifyTargetList = true;
+ }
} while (attr->attisdropped);
tuplogcols++;
format_type_be(tletype),
format_type_be(atttype),
tuplogcols)));
- if (insertRelabels && tletype != atttype)
- tle->expr = (Expr *) makeRelabelType(tle->expr,
- atttype,
- -1,
- COERCE_DONTCARE);
+ if (modifyTargetList)
+ {
+ if (tletype != atttype)
+ {
+ tle->expr = (Expr *) makeRelabelType(tle->expr,
+ atttype,
+ -1,
+ COERCE_DONTCARE);
+ /* Relabel is dangerous if sort/group or setop column */
+ if (tle->ressortgroupref != 0 || parse->setOperations)
+ *modifyTargetList = true;
+ }
+ tle->resno = colindex;
+ newtlist = lappend(newtlist, tle);
+ }
}
- for (;;)
+ /* remaining columns in tupdesc had better all be dropped */
+ for (colindex++; colindex <= tupnatts; colindex++)
{
- colindex++;
- if (colindex > tupnatts)
- break;
if (!tupdesc->attrs[colindex - 1]->attisdropped)
- tuplogcols++;
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
+ errmsg("return type mismatch in function declared to return %s",
+ format_type_be(rettype)),
+ errdetail("Final statement returns too few columns.")));
+ if (modifyTargetList)
+ {
+ Expr *null_expr;
+
+ /* The type of the null we insert isn't important */
+ null_expr = (Expr *) makeConst(INT4OID,
+ -1,
+ sizeof(int32),
+ (Datum) 0,
+ true, /* isnull */
+ true /* byval */ );
+ newtlist = lappend(newtlist,
+ makeTargetEntry(null_expr,
+ colindex,
+ NULL,
+ false));
+ /* NULL insertion is dangerous in a setop */
+ if (parse->setOperations)
+ *modifyTargetList = true;
+ }
}
- if (tlistlen != tuplogcols)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
- errmsg("return type mismatch in function declared to return %s",
- format_type_be(rettype)),
- errdetail("Final statement returns too few columns.")));
+ if (modifyTargetList)
+ {
+ /* ensure resjunk columns are numbered correctly */
+ foreach(lc, junkattrs)
+ {
+ TargetEntry *tle = (TargetEntry *) lfirst(lc);
+
+ tle->resno = colindex++;
+ }
+ /* replace the tlist with the modified one */
+ *tlist_ptr = list_concat(newtlist, junkattrs);
+ }
/* Set up junk filter if needed */
if (junkFilter)
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.279 2009/10/08 02:39:21 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/optimizer/util/clauses.c,v 1.280 2009/12/14 02:15:52 tgl Exp $
*
* HISTORY
* AUTHOR DATE MAJOR EVENT
char *src;
Datum tmp;
bool isNull;
+ bool modifyTargetList;
MemoryContext oldcxt;
MemoryContext mycxt;
ErrorContextCallback sqlerrcontext;
* needed; that's probably not important, but let's be careful.
*/
if (check_sql_fn_retval(funcid, result_type, list_make1(querytree),
- true, NULL))
+ &modifyTargetList, NULL))
goto fail; /* reject whole-tuple-result cases */
/* Now we can grab the tlist expression */
/* Assert that check_sql_fn_retval did the right thing */
Assert(exprType(newexpr) == result_type);
+ /* It couldn't have made any dangerous tlist changes, either */
+ Assert(!modifyTargetList);
/*
* Additional validity checks on the expression. It mustn't return a set,
char *src;
Datum tmp;
bool isNull;
+ bool modifyTargetList;
MemoryContext oldcxt;
MemoryContext mycxt;
ErrorContextCallback sqlerrcontext;
* Make sure the function (still) returns what it's declared to. This
* will raise an error if wrong, but that's okay since the function would
* fail at runtime anyway. Note that check_sql_fn_retval will also insert
- * RelabelType(s) if needed to make the tlist expression(s) match the
- * declared type of the function.
+ * RelabelType(s) and/or NULL columns if needed to make the tlist
+ * expression(s) match the declared type of the function.
*
* If the function returns a composite type, don't inline unless the check
* shows it's returning a whole tuple result; otherwise what it's
*/
if (!check_sql_fn_retval(func_oid, fexpr->funcresulttype,
querytree_list,
- true, NULL) &&
+ &modifyTargetList, NULL) &&
(get_typtype(fexpr->funcresulttype) == TYPTYPE_COMPOSITE ||
fexpr->funcresulttype == RECORDOID))
goto fail; /* reject not-whole-tuple-result cases */
+ /*
+ * If we had to modify the tlist to make it match, and the statement is
+ * one in which changing the tlist contents could change semantics, we
+ * have to punt and not inline.
+ */
+ if (modifyTargetList)
+ goto fail;
+
/*
* If it returns RECORD, we have to check against the column type list
* provided in the RTE; check_sql_fn_retval can't do that. (If no match,
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