Add support for IN as alternative to FROM in PL/PgSQL's FETCH statement,

Neil Conway · Neil Conway · commit f2321a3f37b7 · 2007-04-28T23:54:59.000Z
for consistency with the backend's FETCH command. Patch from Pavel
Stehule, reviewed by Neil Conway.
diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml
@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/plpgsql.sgml,v 1.107 2007/04/16 17:21:22 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/plpgsql.sgml,v 1.108 2007/04/28 23:54:58 neilc Exp $ -->
 
 <chapter id="plpgsql"> 
   <title><application>PL/pgSQL</application> - <acronym>SQL</acronym> Procedural Language</title>
@@ -2523,7 +2523,7 @@ OPEN curs3(42);
      <title><literal>FETCH</></title>
 
 <synopsis>
-FETCH <optional> <replaceable>direction</replaceable> FROM </optional> <replaceable>cursor</replaceable> INTO <replaceable>target</replaceable>;
+FETCH <optional> <replaceable>direction</replaceable> { FROM | IN } </optional> <replaceable>cursor</replaceable> INTO <replaceable>target</replaceable>;
 </synopsis>
 
     <para>
diff --git a/src/pl/plpgsql/src/gram.y b/src/pl/plpgsql/src/gram.y
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.100 2007/04/16 17:21:23 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.101 2007/04/28 23:54:59 neilc Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -2043,13 +2043,15 @@ read_fetch_direction(void)
 	else if (pg_strcasecmp(yytext, "absolute") == 0)
 	{
 		fetch->direction = FETCH_ABSOLUTE;
-		fetch->expr = plpgsql_read_expression(K_FROM, "FROM");
+		fetch->expr = read_sql_construct(K_FROM, K_IN, "FROM or IN",
+										 "SELECT ", true, true, NULL);
 		check_FROM = false;
 	}
 	else if (pg_strcasecmp(yytext, "relative") == 0)
 	{
 		fetch->direction = FETCH_RELATIVE;
-		fetch->expr = plpgsql_read_expression(K_FROM, "FROM");
+		fetch->expr = read_sql_construct(K_FROM, K_IN, "FROM or IN",
+										 "SELECT ", true, true, NULL);
 		check_FROM = false;
 	}
 	else if (pg_strcasecmp(yytext, "forward") == 0)
@@ -2060,16 +2062,27 @@ read_fetch_direction(void)
 	{
 		fetch->direction = FETCH_BACKWARD;
 	}
+	else if (tok != T_SCALAR)
+	{
+		plpgsql_push_back_token(tok);
+		fetch->expr = read_sql_construct(K_FROM, K_IN, "FROM or IN",
+										 "SELECT ", true, true, NULL);
+		check_FROM = false;
+	}
 	else
 	{
 		/* Assume there's no direction clause */
 		plpgsql_push_back_token(tok);
 		check_FROM = false;
 	}
 
-	/* check FROM keyword after direction's specification */
-	if (check_FROM && yylex() != K_FROM)
-		yyerror("expected \"FROM\"");
+	/* check FROM or IN keyword after direction's specification */
+	if (check_FROM)
+	{
+		tok = yylex();
+		if (tok != K_FROM && tok != K_IN)
+			yyerror("expected FROM or IN");
+	}
 
 	return fetch;
 }
diff --git a/src/test/regress/expected/plpgsql.out b/src/test/regress/expected/plpgsql.out
@@ -2245,7 +2245,7 @@ select refcursor_test1('test1');
  test1
 (1 row)
 
-fetch next from test1;
+fetch next in test1;
  a 
 ---
  5
diff --git a/src/test/regress/sql/plpgsql.sql b/src/test/regress/sql/plpgsql.sql
@@ -1918,7 +1918,7 @@ $$ language plpgsql;
 begin;
 
 select refcursor_test1('test1');
-fetch next from test1;
+fetch next in test1;
 
 select refcursor_test1('test2');
 fetch all from test2;

Original file line number	Diff line number	Diff line change
`@@ -9,7 +9,7 @@`
`9`	`9`	`*`
`10`	`10`	`*`
`11`	`11`	`* IDENTIFICATION`
`12`		`- * $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.100 2007/04/16 17:21:23 tgl Exp $`
	`12`	`+ * $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.101 2007/04/28 23:54:59 neilc Exp $`
`13`	`13`	`*`
`14`	`14`	`*-------------------------------------------------------------------------`
`15`	`15`	`*/`
`@@ -2043,13 +2043,15 @@ read_fetch_direction(void)`
`2043`	`2043`	`else if (pg_strcasecmp(yytext, "absolute") == 0)`
`2044`	`2044`	`{`
`2045`	`2045`	`fetch->direction = FETCH_ABSOLUTE;`
`2046`		`- fetch->expr = plpgsql_read_expression(K_FROM, "FROM");`
	`2046`	`+ fetch->expr = read_sql_construct(K_FROM, K_IN, "FROM or IN",`
	`2047`	`+ "SELECT ", true, true, NULL);`
`2047`	`2048`	`check_FROM = false;`
`2048`	`2049`	`}`
`2049`	`2050`	`else if (pg_strcasecmp(yytext, "relative") == 0)`
`2050`	`2051`	`{`
`2051`	`2052`	`fetch->direction = FETCH_RELATIVE;`
`2052`		`- fetch->expr = plpgsql_read_expression(K_FROM, "FROM");`
	`2053`	`+ fetch->expr = read_sql_construct(K_FROM, K_IN, "FROM or IN",`
	`2054`	`+ "SELECT ", true, true, NULL);`
`2053`	`2055`	`check_FROM = false;`
`2054`	`2056`	`}`
`2055`	`2057`	`else if (pg_strcasecmp(yytext, "forward") == 0)`
`@@ -2060,16 +2062,27 @@ read_fetch_direction(void)`
`2060`	`2062`	`{`
`2061`	`2063`	`fetch->direction = FETCH_BACKWARD;`
`2062`	`2064`	`}`
	`2065`	`+ else if (tok != T_SCALAR)`
	`2066`	`+ {`
	`2067`	`+ plpgsql_push_back_token(tok);`
	`2068`	`+ fetch->expr = read_sql_construct(K_FROM, K_IN, "FROM or IN",`
	`2069`	`+ "SELECT ", true, true, NULL);`
	`2070`	`+ check_FROM = false;`
	`2071`	`+ }`
`2063`	`2072`	`else`
`2064`	`2073`	`{`
`2065`	`2074`	`/* Assume there's no direction clause */`
`2066`	`2075`	`plpgsql_push_back_token(tok);`
`2067`	`2076`	`check_FROM = false;`
`2068`	`2077`	`}`
`2069`	`2078`
`2070`		`- /* check FROM keyword after direction's specification */`
`2071`		`- if (check_FROM && yylex() != K_FROM)`
`2072`		`- yyerror("expected \"FROM\"");`
	`2079`	`+ /* check FROM or IN keyword after direction's specification */`
	`2080`	`+ if (check_FROM)`
	`2081`	`+ {`
	`2082`	`+ tok = yylex();`
	`2083`	`+ if (tok != K_FROM && tok != K_IN)`
	`2084`	`+ yyerror("expected FROM or IN");`
	`2085`	`+ }`
`2073`	`2086`
`2074`	`2087`	`return fetch;`
`2075`	`2088`	`}`
Original file line number	Diff line number	Diff line change
`@@ -2245,7 +2245,7 @@ select refcursor_test1('test1');`
`2245`	`2245`	`test1`
`2246`	`2246`	`(1 row)`
`2247`	`2247`
`2248`		`-fetch next from test1;`
	`2248`	`+fetch next in test1;`
`2249`	`2249`	`a`
`2250`	`2250`	`---`
`2251`	`2251`	`5`