From a19002d4e5da028ff7280554b281e402c609898b Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Sat, 9 Apr 2011 14:40:09 -0400
Subject: [PATCH] Adjust collation determination rules as per discussion.
Remove crude hack that tried to propagate collation through a
function-returning-record, ie, from the function's arguments to individual
fields selected from its result record. That is just plain inconsistent,
because the function result is composite and cannot have a collation;
and there's no hope of making this kind of action-at-a-distance work
consistently. Adjust regression test cases that expected this to happen.
Meanwhile, the behavior of casting to a domain with a declared collation
stays the same as it was, since that seemed to be the consensus.
---
src/backend/parser/parse_collate.c | 27 ++--------
src/backend/parser/parse_func.c | 2 +-
src/backend/parser/parse_target.c | 2 +-
.../regress/expected/collate.linux.utf8.out | 54 +++++++++----------
src/test/regress/expected/collate.out | 32 +++++------
src/test/regress/sql/collate.linux.utf8.sql | 10 ++--
src/test/regress/sql/collate.sql | 8 +--
7 files changed, 59 insertions(+), 76 deletions(-)
diff --git a/src/backend/parser/parse_collate.c b/src/backend/parser/parse_collate.c
index 8860679ccb9..3e557db2668 100644
--- a/src/backend/parser/parse_collate.c
+++ b/src/backend/parser/parse_collate.c
@@ -289,10 +289,11 @@ assign_collations_walker(Node *node, assign_collations_context *context)
case T_FieldSelect:
{
/*
- * FieldSelect is a special case because the field may have
- * a non-default collation, in which case we should use that.
- * The field's collation was already looked up and saved
- * in the node.
+ * For FieldSelect, the result has the field's declared
+ * collation, independently of what happened in the arguments.
+ * (The immediate argument must be composite and thus not
+ * collatable, anyhow.) The field's collation was already
+ * looked up and saved in the node.
*/
FieldSelect *expr = (FieldSelect *) node;
@@ -304,24 +305,6 @@ assign_collations_walker(Node *node, assign_collations_context *context)
if (OidIsValid(expr->resultcollid))
{
/* Node's result type is collatable. */
- if (expr->resultcollid == DEFAULT_COLLATION_OID)
- {
- /*
- * The immediate input node necessarily yields a
- * composite type, so it will have no exposed
- * collation. However, if we are selecting a field
- * from a function returning composite, see if we
- * can bubble up a collation from the function's
- * input. XXX this is a bit of a hack, rethink ...
- */
- if (IsA(expr->arg, FuncExpr))
- {
- FuncExpr *fexpr = (FuncExpr *) expr->arg;
-
- if (OidIsValid(fexpr->inputcollid))
- expr->resultcollid = fexpr->inputcollid;
- }
- }
/* Pass up field's collation as an implicit choice. */
collation = expr->resultcollid;
strength = COLLATE_IMPLICIT;
diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c
index a187287e283..ba699e9a1ed 100644
--- a/src/backend/parser/parse_func.c
+++ b/src/backend/parser/parse_func.c
@@ -1384,7 +1384,7 @@ ParseComplexProjection(ParseState *pstate, char *funcname, Node *first_arg,
fselect->fieldnum = i + 1;
fselect->resulttype = att->atttypid;
fselect->resulttypmod = att->atttypmod;
- /* resultcollid may get overridden by parse_collate.c */
+ /* save attribute's collation for parse_collate.c */
fselect->resultcollid = att->attcollation;
return (Node *) fselect;
}
diff --git a/src/backend/parser/parse_target.c b/src/backend/parser/parse_target.c
index d53d1d9f008..52c6db2eb5c 100644
--- a/src/backend/parser/parse_target.c
+++ b/src/backend/parser/parse_target.c
@@ -1290,7 +1290,7 @@ ExpandRowReference(ParseState *pstate, Node *expr,
fselect->fieldnum = i + 1;
fselect->resulttype = att->atttypid;
fselect->resulttypmod = att->atttypmod;
- /* resultcollid may get overridden by parse_collate.c */
+ /* save attribute's collation for parse_collate.c */
fselect->resultcollid = att->attcollation;
if (targetlist)
diff --git a/src/test/regress/expected/collate.linux.utf8.out b/src/test/regress/expected/collate.linux.utf8.out
index a4ec1e90801..fe4d27e34b1 100644
--- a/src/test/regress/expected/collate.linux.utf8.out
+++ b/src/test/regress/expected/collate.linux.utf8.out
@@ -771,33 +771,33 @@ SELECT * FROM unnest((SELECT array_agg(b ORDER BY b) FROM collate_test3)) ORDER
äbc
(4 rows)
-CREATE FUNCTION dup (f1 anyelement, f2 out anyelement, f3 out anyarray)
- AS 'select $1, array[$1,$1]' LANGUAGE sql;
-SELECT a, (dup(b)).* FROM collate_test1 ORDER BY 2;
- a | f2 | f3
----+-----+-----------
- 1 | abc | {abc,abc}
- 4 | ABC | {ABC,ABC}
- 2 | äbc | {äbc,äbc}
- 3 | bbc | {bbc,bbc}
-(4 rows)
-
-SELECT a, (dup(b)).* FROM collate_test2 ORDER BY 2;
- a | f2 | f3
----+-----+-----------
- 1 | abc | {abc,abc}
- 4 | ABC | {ABC,ABC}
- 3 | bbc | {bbc,bbc}
- 2 | äbc | {äbc,äbc}
-(4 rows)
-
-SELECT a, (dup(b)).* FROM collate_test3 ORDER BY 2;
- a | f2 | f3
----+-----+-----------
- 4 | ABC | {ABC,ABC}
- 1 | abc | {abc,abc}
- 3 | bbc | {bbc,bbc}
- 2 | äbc | {äbc,äbc}
+CREATE FUNCTION dup (anyelement) RETURNS anyelement
+ AS 'select $1' LANGUAGE sql;
+SELECT a, dup(b) FROM collate_test1 ORDER BY 2;
+ a | dup
+---+-----
+ 1 | abc
+ 4 | ABC
+ 2 | äbc
+ 3 | bbc
+(4 rows)
+
+SELECT a, dup(b) FROM collate_test2 ORDER BY 2;
+ a | dup
+---+-----
+ 1 | abc
+ 4 | ABC
+ 3 | bbc
+ 2 | äbc
+(4 rows)
+
+SELECT a, dup(b) FROM collate_test3 ORDER BY 2;
+ a | dup
+---+-----
+ 4 | ABC
+ 1 | abc
+ 3 | bbc
+ 2 | äbc
(4 rows)
-- indexes
diff --git a/src/test/regress/expected/collate.out b/src/test/regress/expected/collate.out
index f1a025ae373..230eb9ef315 100644
--- a/src/test/regress/expected/collate.out
+++ b/src/test/regress/expected/collate.out
@@ -502,24 +502,24 @@ SELECT * FROM unnest((SELECT array_agg(b ORDER BY b) FROM collate_test2)) ORDER
bbc
(4 rows)
-CREATE FUNCTION dup (f1 anyelement, f2 out anyelement, f3 out anyarray)
- AS 'select $1, array[$1,$1]' LANGUAGE sql;
-SELECT a, (dup(b)).* FROM collate_test1 ORDER BY 2;
- a | f2 | f3
----+-----+-----------
- 4 | ABD | {ABD,ABD}
- 2 | Abc | {Abc,Abc}
- 1 | abc | {abc,abc}
- 3 | bbc | {bbc,bbc}
+CREATE FUNCTION dup (anyelement) RETURNS anyelement
+ AS 'select $1' LANGUAGE sql;
+SELECT a, dup(b) FROM collate_test1 ORDER BY 2;
+ a | dup
+---+-----
+ 4 | ABD
+ 2 | Abc
+ 1 | abc
+ 3 | bbc
(4 rows)
-SELECT a, (dup(b)).* FROM collate_test2 ORDER BY 2;
- a | f2 | f3
----+-----+-----------
- 4 | ABD | {ABD,ABD}
- 2 | Abc | {Abc,Abc}
- 1 | abc | {abc,abc}
- 3 | bbc | {bbc,bbc}
+SELECT a, dup(b) FROM collate_test2 ORDER BY 2;
+ a | dup
+---+-----
+ 4 | ABD
+ 2 | Abc
+ 1 | abc
+ 3 | bbc
(4 rows)
-- indexes
diff --git a/src/test/regress/sql/collate.linux.utf8.sql b/src/test/regress/sql/collate.linux.utf8.sql
index 265db722202..57f5947aa9d 100644
--- a/src/test/regress/sql/collate.linux.utf8.sql
+++ b/src/test/regress/sql/collate.linux.utf8.sql
@@ -242,12 +242,12 @@ SELECT * FROM unnest((SELECT array_agg(b ORDER BY b) FROM collate_test1)) ORDER
SELECT * FROM unnest((SELECT array_agg(b ORDER BY b) FROM collate_test2)) ORDER BY 1;
SELECT * FROM unnest((SELECT array_agg(b ORDER BY b) FROM collate_test3)) ORDER BY 1;
-CREATE FUNCTION dup (f1 anyelement, f2 out anyelement, f3 out anyarray)
- AS 'select $1, array[$1,$1]' LANGUAGE sql;
+CREATE FUNCTION dup (anyelement) RETURNS anyelement
+ AS 'select $1' LANGUAGE sql;
-SELECT a, (dup(b)).* FROM collate_test1 ORDER BY 2;
-SELECT a, (dup(b)).* FROM collate_test2 ORDER BY 2;
-SELECT a, (dup(b)).* FROM collate_test3 ORDER BY 2;
+SELECT a, dup(b) FROM collate_test1 ORDER BY 2;
+SELECT a, dup(b) FROM collate_test2 ORDER BY 2;
+SELECT a, dup(b) FROM collate_test3 ORDER BY 2;
-- indexes
diff --git a/src/test/regress/sql/collate.sql b/src/test/regress/sql/collate.sql
index c904aa77f37..39c22674b9c 100644
--- a/src/test/regress/sql/collate.sql
+++ b/src/test/regress/sql/collate.sql
@@ -168,11 +168,11 @@ SELECT a, CAST(b AS varchar) FROM collate_test2 ORDER BY 2;
SELECT * FROM unnest((SELECT array_agg(b ORDER BY b) FROM collate_test1)) ORDER BY 1;
SELECT * FROM unnest((SELECT array_agg(b ORDER BY b) FROM collate_test2)) ORDER BY 1;
-CREATE FUNCTION dup (f1 anyelement, f2 out anyelement, f3 out anyarray)
- AS 'select $1, array[$1,$1]' LANGUAGE sql;
+CREATE FUNCTION dup (anyelement) RETURNS anyelement
+ AS 'select $1' LANGUAGE sql;
-SELECT a, (dup(b)).* FROM collate_test1 ORDER BY 2;
-SELECT a, (dup(b)).* FROM collate_test2 ORDER BY 2;
+SELECT a, dup(b) FROM collate_test1 ORDER BY 2;
+SELECT a, dup(b) FROM collate_test2 ORDER BY 2;
-- indexes
--
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