From 470a1048ec145fe16b5baea56b9aef93f9878747 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Sun, 1 Sep 2002 16:28:06 +0000
Subject: [PATCH] plpgsql functions can return RECORD, per Neil Conway.
---
doc/src/sgml/plpgsql.sgml | 4 +-
doc/src/sgml/xfunc.sgml | 23 +++++++++++-
src/pl/plpgsql/src/gram.y | 3 +-
src/pl/plpgsql/src/pl_comp.c | 14 +++----
src/pl/plpgsql/src/pl_exec.c | 8 ++--
src/test/regress/expected/plpgsql.out | 53 +++++++++++++++++++++++++++
src/test/regress/sql/plpgsql.sql | 35 ++++++++++++++++++
7 files changed, 123 insertions(+), 17 deletions(-)
diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
index 4da3f3c0405..998ed72089e 100644
--- a/doc/src/sgml/plpgsql.sgml
+++ b/doc/src/sgml/plpgsql.sgml
@@ -1,5 +1,5 @@
<!--
-$Header: /cvsroot/pgsql/doc/src/sgml/plpgsql.sgml,v 1.5 2002/08/30 00:28:40 tgl Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/plpgsql.sgml,v 1.6 2002/09/01 16:28:05 tgl Exp $
-->
<chapter id="plpgsql">
@@ -538,8 +538,6 @@ END;
<para>
Note that <literal>RECORD</> is not a true data type, only a placeholder.
- Thus, for example, one cannot declare a function returning
- <literal>RECORD</>.
</para>
</sect2>
diff --git a/doc/src/sgml/xfunc.sgml b/doc/src/sgml/xfunc.sgml
index 9a7b79f0ddd..3999bf81769 100644
--- a/doc/src/sgml/xfunc.sgml
+++ b/doc/src/sgml/xfunc.sgml
@@ -1,5 +1,5 @@
<!--
-$Header: /cvsroot/pgsql/doc/src/sgml/xfunc.sgml,v 1.59 2002/08/30 00:28:40 tgl Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/xfunc.sgml,v 1.60 2002/09/01 16:28:05 tgl Exp $
-->
<chapter id="xfunc">
@@ -2119,6 +2119,27 @@ SELECT * FROM vw_getfoo;
</programlisting>
are all valid statements.
</para>
+
+ <para>
+ In some cases it is useful to define table functions that can return
+ different column sets depending on how they are invoked. To support this,
+ the table function can be declared as returning the pseudo-type
+ <type>record</>. When such a function is used in a query, the expected
+ row structure must be specified in the query itself, so that the system
+ can know how to parse and plan the query. Consider this example:
+<programlisting>
+SELECT *
+FROM dblink('dbname=template1', 'select proname, prosrc from pg_proc')
+ AS t1(proname name, prosrc text)
+WHERE proname LIKE 'bytea%';
+</programlisting>
+ The <literal>dblink</> function executes a remote query (see
+ <literal>contrib/dblink</>). It is declared to return <type>record</>
+ since it might be used for any kind of query. The actual column set
+ must be specified in the calling query so that the parser knows, for
+ example, what <literal>*</> should expand to.
+ </para>
+
</sect1>
<sect1 id="xfunc-plhandler">
diff --git a/src/pl/plpgsql/src/gram.y b/src/pl/plpgsql/src/gram.y
index 47c8a9c1919..7c62d66d243 100644
--- a/src/pl/plpgsql/src/gram.y
+++ b/src/pl/plpgsql/src/gram.y
@@ -4,7 +4,7 @@
* procedural language
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/pl/plpgsql/src/gram.y,v 1.36 2002/08/30 00:28:41 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/pl/plpgsql/src/gram.y,v 1.37 2002/09/01 16:28:06 tgl Exp $
*
* This software is copyrighted by Jan Wieck - Hamburg.
*
@@ -1159,7 +1159,6 @@ stmt_return : K_RETURN lno
}
;
-/* FIXME: this syntax needs work, RETURN NEXT breaks stmt_return */
stmt_return_next: K_RETURN_NEXT lno
{
PLpgSQL_stmt_return_next *new;
diff --git a/src/pl/plpgsql/src/pl_comp.c b/src/pl/plpgsql/src/pl_comp.c
index 1878c5e396e..2ee06acbe0b 100644
--- a/src/pl/plpgsql/src/pl_comp.c
+++ b/src/pl/plpgsql/src/pl_comp.c
@@ -3,7 +3,7 @@
* procedural language
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/pl/plpgsql/src/pl_comp.c,v 1.49 2002/08/30 00:28:41 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/pl/plpgsql/src/pl_comp.c,v 1.50 2002/09/01 16:28:06 tgl Exp $
*
* This software is copyrighted by Jan Wieck - Hamburg.
*
@@ -211,11 +211,11 @@ plpgsql_compile(Oid fn_oid, int functype)
procStruct->prorettype);
typeStruct = (Form_pg_type) GETSTRUCT(typeTup);
- /* Disallow pseudotype result, except VOID */
- /* XXX someday allow RECORD? */
+ /* Disallow pseudotype result, except VOID or RECORD */
if (typeStruct->typtype == 'p')
{
- if (procStruct->prorettype == VOIDOID)
+ if (procStruct->prorettype == VOIDOID ||
+ procStruct->prorettype == RECORDOID)
/* okay */;
else if (procStruct->prorettype == TRIGGEROID ||
procStruct->prorettype == OPAQUEOID)
@@ -227,7 +227,8 @@ plpgsql_compile(Oid fn_oid, int functype)
format_type_be(procStruct->prorettype));
}
- if (typeStruct->typrelid != InvalidOid)
+ if (typeStruct->typrelid != InvalidOid ||
+ procStruct->prorettype == RECORDOID)
function->fn_retistuple = true;
else
{
@@ -486,8 +487,7 @@ plpgsql_compile(Oid fn_oid, int functype)
}
/*
- * Create the magic found variable indicating if the last FOR or
- * SELECT statement returned data
+ * Create the magic FOUND variable.
*/
var = malloc(sizeof(PLpgSQL_var));
memset(var, 0, sizeof(PLpgSQL_var));
diff --git a/src/pl/plpgsql/src/pl_exec.c b/src/pl/plpgsql/src/pl_exec.c
index 6f52f2c0480..7b7b1c1555e 100644
--- a/src/pl/plpgsql/src/pl_exec.c
+++ b/src/pl/plpgsql/src/pl_exec.c
@@ -3,7 +3,7 @@
* procedural language
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/pl/plpgsql/src/pl_exec.c,v 1.61 2002/08/30 23:59:46 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/pl/plpgsql/src/pl_exec.c,v 1.62 2002/09/01 16:28:06 tgl Exp $
*
* This software is copyrighted by Jan Wieck - Hamburg.
*
@@ -1588,9 +1588,9 @@ static int
exec_stmt_return_next(PLpgSQL_execstate *estate,
PLpgSQL_stmt_return_next *stmt)
{
- TupleDesc tupdesc;
- int natts;
- HeapTuple tuple;
+ TupleDesc tupdesc;
+ int natts;
+ HeapTuple tuple;
bool free_tuple = false;
if (!estate->retisset)
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
index 583543262ed..e18a1d556a6 100644
--- a/src/test/regress/expected/plpgsql.out
+++ b/src/test/regress/expected/plpgsql.out
@@ -1680,3 +1680,56 @@ select * from test_ret_set_scalar(1,10);
11
(10 rows)
+create function test_ret_set_rec_dyn(int) returns setof record as '
+DECLARE
+ retval RECORD;
+BEGIN
+ IF $1 > 10 THEN
+ SELECT INTO retval 5, 10, 15;
+ RETURN NEXT retval;
+ RETURN NEXT retval;
+ ELSE
+ SELECT INTO retval 50, 5::numeric, ''xxx''::text;
+ RETURN NEXT retval;
+ RETURN NEXT retval;
+ END IF;
+ RETURN;
+END;' language 'plpgsql';
+SELECT * FROM test_ret_set_rec_dyn(1500) AS (a int, b int, c int);
+ a | b | c
+---+----+----
+ 5 | 10 | 15
+ 5 | 10 | 15
+(2 rows)
+
+SELECT * FROM test_ret_set_rec_dyn(5) AS (a int, b numeric, c text);
+ a | b | c
+----+---+-----
+ 50 | 5 | xxx
+ 50 | 5 | xxx
+(2 rows)
+
+create function test_ret_rec_dyn(int) returns record as '
+DECLARE
+ retval RECORD;
+BEGIN
+ IF $1 > 10 THEN
+ SELECT INTO retval 5, 10, 15;
+ RETURN retval;
+ ELSE
+ SELECT INTO retval 50, 5::numeric, ''xxx''::text;
+ RETURN retval;
+ END IF;
+END;' language 'plpgsql';
+SELECT * FROM test_ret_rec_dyn(1500) AS (a int, b int, c int);
+ a | b | c
+---+----+----
+ 5 | 10 | 15
+(1 row)
+
+SELECT * FROM test_ret_rec_dyn(5) AS (a int, b numeric, c text);
+ a | b | c
+----+---+-----
+ 50 | 5 | xxx
+(1 row)
+
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
index e6795ed10a6..b6607442d72 100644
--- a/src/test/regress/sql/plpgsql.sql
+++ b/src/test/regress/sql/plpgsql.sql
@@ -1524,3 +1524,38 @@ BEGIN
END;' language 'plpgsql';
select * from test_ret_set_scalar(1,10);
+
+create function test_ret_set_rec_dyn(int) returns setof record as '
+DECLARE
+ retval RECORD;
+BEGIN
+ IF $1 > 10 THEN
+ SELECT INTO retval 5, 10, 15;
+ RETURN NEXT retval;
+ RETURN NEXT retval;
+ ELSE
+ SELECT INTO retval 50, 5::numeric, ''xxx''::text;
+ RETURN NEXT retval;
+ RETURN NEXT retval;
+ END IF;
+ RETURN;
+END;' language 'plpgsql';
+
+SELECT * FROM test_ret_set_rec_dyn(1500) AS (a int, b int, c int);
+SELECT * FROM test_ret_set_rec_dyn(5) AS (a int, b numeric, c text);
+
+create function test_ret_rec_dyn(int) returns record as '
+DECLARE
+ retval RECORD;
+BEGIN
+ IF $1 > 10 THEN
+ SELECT INTO retval 5, 10, 15;
+ RETURN retval;
+ ELSE
+ SELECT INTO retval 50, 5::numeric, ''xxx''::text;
+ RETURN retval;
+ END IF;
+END;' language 'plpgsql';
+
+SELECT * FROM test_ret_rec_dyn(1500) AS (a int, b int, c int);
+SELECT * FROM test_ret_rec_dyn(5) AS (a int, b numeric, c text);
--
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