mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-10-01 12:01:24 +02:00
Allow extracting fields from a ROW() expression in more cases.
Teach get_expr_result_type() to manufacture a tuple descriptor directly from a RowExpr node. If the RowExpr has type RECORD, this is the only way to get a tupdesc for its result, since even if the rowtype has been blessed, we don't have its typmod available at this point. (If the RowExpr has some named composite type, we continue to let the existing code handle it, since the RowExpr might well not have the correct column names embedded in it.) This fixes assorted corner cases illustrated by the added regression tests. Discussion: https://postgr.es/m/10872.1572202006@sss.pgh.pa.us
This commit is contained in:
parent
f88544904e
commit
8b7a0f1d11
@ -227,6 +227,38 @@ get_expr_result_type(Node *expr,
|
||||
NULL,
|
||||
resultTypeId,
|
||||
resultTupleDesc);
|
||||
else if (expr && IsA(expr, RowExpr) &&
|
||||
((RowExpr *) expr)->row_typeid == RECORDOID)
|
||||
{
|
||||
/* We can resolve the record type by generating the tupdesc directly */
|
||||
RowExpr *rexpr = (RowExpr *) expr;
|
||||
TupleDesc tupdesc;
|
||||
AttrNumber i = 1;
|
||||
ListCell *lcc,
|
||||
*lcn;
|
||||
|
||||
tupdesc = CreateTemplateTupleDesc(list_length(rexpr->args));
|
||||
Assert(list_length(rexpr->args) == list_length(rexpr->colnames));
|
||||
forboth(lcc, rexpr->args, lcn, rexpr->colnames)
|
||||
{
|
||||
Node *col = (Node *) lfirst(lcc);
|
||||
char *colname = strVal(lfirst(lcn));
|
||||
|
||||
TupleDescInitEntry(tupdesc, i,
|
||||
colname,
|
||||
exprType(col),
|
||||
exprTypmod(col),
|
||||
0);
|
||||
TupleDescInitEntryCollation(tupdesc, i,
|
||||
exprCollation(col));
|
||||
i++;
|
||||
}
|
||||
if (resultTypeId)
|
||||
*resultTypeId = rexpr->row_typeid;
|
||||
if (resultTupleDesc)
|
||||
*resultTupleDesc = BlessTupleDesc(tupdesc);
|
||||
return TYPEFUNC_COMPOSITE;
|
||||
}
|
||||
else
|
||||
{
|
||||
/* handle as a generic expression; no chance to resolve RECORD */
|
||||
|
@ -436,6 +436,45 @@ where i8 in (row(123,456)::int8_tbl, '(4567890123456789,123)');
|
||||
4567890123456789 | 123
|
||||
(2 rows)
|
||||
|
||||
-- Check ability to select columns from an anonymous rowtype
|
||||
select (row(1, 2.0)).f1;
|
||||
f1
|
||||
----
|
||||
1
|
||||
(1 row)
|
||||
|
||||
select (row(1, 2.0)).f2;
|
||||
f2
|
||||
-----
|
||||
2.0
|
||||
(1 row)
|
||||
|
||||
select (row(1, 2.0)).nosuch; -- fail
|
||||
ERROR: could not identify column "nosuch" in record data type
|
||||
LINE 1: select (row(1, 2.0)).nosuch;
|
||||
^
|
||||
select (row(1, 2.0)).*;
|
||||
f1 | f2
|
||||
----+-----
|
||||
1 | 2.0
|
||||
(1 row)
|
||||
|
||||
select (r).f1 from (select row(1, 2.0) as r) ss;
|
||||
f1
|
||||
----
|
||||
1
|
||||
(1 row)
|
||||
|
||||
select (r).f3 from (select row(1, 2.0) as r) ss; -- fail
|
||||
ERROR: could not identify column "f3" in record data type
|
||||
LINE 1: select (r).f3 from (select row(1, 2.0) as r) ss;
|
||||
^
|
||||
select (r).* from (select row(1, 2.0) as r) ss;
|
||||
f1 | f2
|
||||
----+-----
|
||||
1 | 2.0
|
||||
(1 row)
|
||||
|
||||
-- Check some corner cases involving empty rowtypes
|
||||
select ROW();
|
||||
row
|
||||
|
@ -171,6 +171,15 @@ where i8 in (row(123,456)::int8_tbl, '(4567890123456789,123)');
|
||||
select * from int8_tbl i8
|
||||
where i8 in (row(123,456)::int8_tbl, '(4567890123456789,123)');
|
||||
|
||||
-- Check ability to select columns from an anonymous rowtype
|
||||
select (row(1, 2.0)).f1;
|
||||
select (row(1, 2.0)).f2;
|
||||
select (row(1, 2.0)).nosuch; -- fail
|
||||
select (row(1, 2.0)).*;
|
||||
select (r).f1 from (select row(1, 2.0) as r) ss;
|
||||
select (r).f3 from (select row(1, 2.0) as r) ss; -- fail
|
||||
select (r).* from (select row(1, 2.0) as r) ss;
|
||||
|
||||
-- Check some corner cases involving empty rowtypes
|
||||
select ROW();
|
||||
select ROW() IS NULL;
|
||||
|
Loading…
Reference in New Issue
Block a user