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Postgres FD Implementation
Commit 347dd6a1 authored by Tom Lane's avatar Tom Lane
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Make plpgsql support FOR over a query specified by a cursor declaration, 

for improved compatibility with Oracle.

Pavel Stehule, with some fixes by me.
parent 26043592
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Showing with 934 additions and 555 deletions
doc/src/sgml/plpgsql.sgml
View file @ 347dd6a1
<!-- $PostgreSQL: pgsql/doc/src/sgml/plpgsql.sgml,v 1.126 2008/04/01 03:51:09 tgl Exp $ --> <!-- $PostgreSQL: pgsql/doc/src/sgml/plpgsql.sgml,v 1.127 2008/04/06 23:43:29 tgl Exp $ -->
<chapter id="plpgsql"> <chapter id="plpgsql">
<title><application>PL/pgSQL</application> - <acronym>SQL</acronym> Procedural Language</title> <title><application>PL/pgSQL</application> - <acronym>SQL</acronym> Procedural Language</title>
...@@ -286,9 +286,11 @@ $$ LANGUAGE plpgsql; ...@@ -286,9 +286,11 @@ $$ LANGUAGE plpgsql;
<para> <para>
All variables used in a block must be declared in the All variables used in a block must be declared in the
declarations section of the block. declarations section of the block.
(The only exception is that the loop variable of a <literal>FOR</> loop (The only exceptions are that the loop variable of a <literal>FOR</> loop
iterating over a range of integer values is automatically declared as an iterating over a range of integer values is automatically declared as an
integer variable.) integer variable, and likewise the loop variable of a <literal>FOR</> loop
iterating over a cursor's result is automatically declared as a
record variable.)
</para> </para>
<para> <para>
...@@ -1317,10 +1319,11 @@ GET DIAGNOSTICS integer_var = ROW_COUNT; ...@@ -1317,10 +1319,11 @@ GET DIAGNOSTICS integer_var = ROW_COUNT;
<para> <para>
A <command>FOR</> statement sets <literal>FOUND</literal> true A <command>FOR</> statement sets <literal>FOUND</literal> true
if it iterates one or more times, else false. This applies to if it iterates one or more times, else false. This applies to
all three variants of the <command>FOR</> statement (integer all four variants of the <command>FOR</> statement (integer
<command>FOR</> loops, record-set <command>FOR</> loops, and <command>FOR</> loops, record-set <command>FOR</> loops,
dynamic record-set <command>FOR</> dynamic record-set <command>FOR</> loops, and cursor
loops). <literal>FOUND</literal> is set this way when the <command>FOR</> loops).
<literal>FOUND</literal> is set this way when the
<command>FOR</> loop exits; inside the execution of the loop, <command>FOR</> loop exits; inside the execution of the loop,
<literal>FOUND</literal> is not modified by the <literal>FOUND</literal> is not modified by the
<command>FOR</> statement, although it might be changed by the <command>FOR</> statement, although it might be changed by the
...@@ -2057,6 +2060,12 @@ END LOOP <optional> <replaceable>label</replaceable> </optional>; ...@@ -2057,6 +2060,12 @@ END LOOP <optional> <replaceable>label</replaceable> </optional>;
As with <command>EXECUTE</command>, parameter values can be inserted As with <command>EXECUTE</command>, parameter values can be inserted
into the dynamic command via <literal>USING</>. into the dynamic command via <literal>USING</>.
</para> </para>
<para>
Another way to specify the query whose results should be iterated
through is to declare it as a cursor. This is described in
<xref linkend="plpgsql-cursor-for-loop">.
</para>
</sect2> </sect2>
<sect2 id="plpgsql-error-trapping"> <sect2 id="plpgsql-error-trapping">
...@@ -2293,6 +2302,14 @@ DECLARE ...@@ -2293,6 +2302,14 @@ DECLARE
cursor variables while the third uses a bound cursor variable. cursor variables while the third uses a bound cursor variable.
</para> </para>
<note>
<para>
Bound cursors can also be used without explicitly opening them,
via the <command>FOR</> statement described in
<xref linkend="plpgsql-cursor-for-loop">.
</para>
</note>
<sect3> <sect3>
<title><command>OPEN FOR</command> <replaceable>query</replaceable></title> <title><command>OPEN FOR</command> <replaceable>query</replaceable></title>
...@@ -2676,6 +2693,36 @@ COMMIT; ...@@ -2676,6 +2693,36 @@ COMMIT;
</para> </para>
</sect3> </sect3>
</sect2> </sect2>
<sect2 id="plpgsql-cursor-for-loop">
<title>Looping Through a Cursor's Result</title>
<para>
There is a variant of the <command>FOR</> statement that allows
iterating through the rows returned by a cursor. The syntax is:
<synopsis>
<optional> &lt;&lt;<replaceable>label</replaceable>&gt;&gt; </optional>
FOR <replaceable>recordvar</replaceable> IN <replaceable>bound_cursor</replaceable> <optional> ( <replaceable>argument_values</replaceable> ) </optional> LOOP
<replaceable>statements</replaceable>
END LOOP <optional> <replaceable>label</replaceable> </optional>;
</synopsis>
The cursor variable must have been bound to some query when it was
declared, and it <emphasis>cannot</> be open already. The
<command>FOR</> statement automatically opens the cursor, and it closes
the cursor again when the loop exits. A list of actual argument value
expressions must appear if and only if the cursor was declared to take
arguments. These values will be substituted in the query, in just
the same way as during an <command>OPEN</>.
The variable <replaceable>recordvar</replaceable> is automatically
defined as type <type>record</> and exists only inside the loop (any
existing definition of the variable name is ignored within the loop).
Each row returned by the cursor is successively assigned to this
record variable and the loop body is executed.
</para>
</sect2>
</sect1> </sect1>
<sect1 id="plpgsql-errors-and-messages"> <sect1 id="plpgsql-errors-and-messages">
...@@ -3796,14 +3843,6 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$ ...@@ -3796,14 +3843,6 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
</para> </para>
</listitem> </listitem>
<listitem>
<para>
No need for cursors in <application>PL/pgSQL</>, just put the
query in the <literal>FOR</literal> statement. (See <xref
linkend="plpgsql-porting-ex2">.)
</para>
</listitem>
<listitem> <listitem>
<para> <para>
In <productname>PostgreSQL</> the function body must be written as In <productname>PostgreSQL</> the function body must be written as
...@@ -3840,6 +3879,23 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$ ...@@ -3840,6 +3879,23 @@ a_output := a_output || $$ if v_$$ || referrer_keys.kind || $$ like '$$
</para> </para>
</listitem> </listitem>
<listitem>
<para>
<command>FOR</> loops over queries (other than cursors) also work
differently: the target variable(s) must have been declared,
whereas <application>PL/SQL</> always declares them implicitly.
An advantage of this is that the variable values are still accessible
after the loop exits.
</para>
</listitem>
<listitem>
<para>
There are various notational differences for the use of cursor
variables.
</para>
</listitem>
</itemizedlist> </itemizedlist>
</para> </para>
...@@ -3939,8 +3995,7 @@ $$ LANGUAGE plpgsql; ...@@ -3939,8 +3995,7 @@ $$ LANGUAGE plpgsql;
The following procedure grabs rows from a The following procedure grabs rows from a
<command>SELECT</command> statement and builds a large function <command>SELECT</command> statement and builds a large function
with the results in <literal>IF</literal> statements, for the with the results in <literal>IF</literal> statements, for the
sake of efficiency. Notice particularly the differences in the sake of efficiency.
cursor and the <literal>FOR</literal> loop.
</para> </para>
<para> <para>
...@@ -3950,7 +4005,6 @@ CREATE OR REPLACE PROCEDURE cs_update_referrer_type_proc IS ...@@ -3950,7 +4005,6 @@ CREATE OR REPLACE PROCEDURE cs_update_referrer_type_proc IS
CURSOR referrer_keys IS CURSOR referrer_keys IS
SELECT * FROM cs_referrer_keys SELECT * FROM cs_referrer_keys
ORDER BY try_order; ORDER BY try_order;
func_cmd VARCHAR(4000); func_cmd VARCHAR(4000);
BEGIN BEGIN
func_cmd := 'CREATE OR REPLACE FUNCTION cs_find_referrer_type(v_host IN VARCHAR, func_cmd := 'CREATE OR REPLACE FUNCTION cs_find_referrer_type(v_host IN VARCHAR,
...@@ -3978,16 +4032,15 @@ show errors; ...@@ -3978,16 +4032,15 @@ show errors;
<programlisting> <programlisting>
CREATE OR REPLACE FUNCTION cs_update_referrer_type_proc() RETURNS void AS $func$ CREATE OR REPLACE FUNCTION cs_update_referrer_type_proc() RETURNS void AS $func$
DECLARE DECLARE
referrer_key RECORD; -- declare a generic record to be used in a FOR CURSOR referrer_keys IS
SELECT * FROM cs_referrer_keys
ORDER BY try_order;
func_body text; func_body text;
func_cmd text; func_cmd text;
BEGIN BEGIN
func_body := 'BEGIN'; func_body := 'BEGIN';
-- Notice how we scan through the results of a query in a FOR loop FOR referrer_key IN referrer_keys LOOP
-- using the FOR &lt;record&gt; construct.
FOR referrer_key IN SELECT * FROM cs_referrer_keys ORDER BY try_order LOOP
func_body := func_body || func_body := func_body ||
' IF v_' || referrer_key.kind ' IF v_' || referrer_key.kind
|| ' LIKE ' || quote_literal(referrer_key.key_string) || ' LIKE ' || quote_literal(referrer_key.key_string)
......
src/pl/plpgsql/src/gram.y
View file @ 347dd6a1
...@@ -9,7 +9,7 @@ ...@@ -9,7 +9,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.109 2008/04/01 03:51:09 tgl Exp $ * $PostgreSQL: pgsql/src/pl/plpgsql/src/gram.y,v 1.110 2008/04/06 23:43:29 tgl Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
...@@ -50,6 +50,8 @@ static void plpgsql_sql_error_callback(void *arg); ...@@ -50,6 +50,8 @@ static void plpgsql_sql_error_callback(void *arg);
static char *check_label(const char *yytxt); static char *check_label(const char *yytxt);
static void check_labels(const char *start_label, static void check_labels(const char *start_label,
const char *end_label); const char *end_label);
static PLpgSQL_expr *read_cursor_args(PLpgSQL_var *cursor,
int until, const char *expected);
%} %}
...@@ -861,21 +863,15 @@ stmt_for : opt_block_label K_FOR for_control loop_body ...@@ -861,21 +863,15 @@ stmt_for : opt_block_label K_FOR for_control loop_body
new->body = $4.stmts; new->body = $4.stmts;
$$ = (PLpgSQL_stmt *) new; $$ = (PLpgSQL_stmt *) new;
} }
else if ($3->cmd_type == PLPGSQL_STMT_FORS)
{
PLpgSQL_stmt_fors *new;
new = (PLpgSQL_stmt_fors *) $3;
new->label = $1;
new->body = $4.stmts;
$$ = (PLpgSQL_stmt *) new;
}
else else
{ {
PLpgSQL_stmt_dynfors *new; PLpgSQL_stmt_forq *new;
Assert($3->cmd_type == PLPGSQL_STMT_DYNFORS); Assert($3->cmd_type == PLPGSQL_STMT_FORS ||
new = (PLpgSQL_stmt_dynfors *) $3; $3->cmd_type == PLPGSQL_STMT_FORC ||
$3->cmd_type == PLPGSQL_STMT_DYNFORS);
/* forq is the common supertype of all three */
new = (PLpgSQL_stmt_forq *) $3;
new->label = $1; new->label = $1;
new->body = $4.stmts; new->body = $4.stmts;
$$ = (PLpgSQL_stmt *) new; $$ = (PLpgSQL_stmt *) new;
...@@ -892,9 +888,9 @@ for_control : ...@@ -892,9 +888,9 @@ for_control :
{ {
int tok = yylex(); int tok = yylex();
/* Simple case: EXECUTE is a dynamic FOR loop */
if (tok == K_EXECUTE) if (tok == K_EXECUTE)
{ {
/* EXECUTE means it's a dynamic FOR loop */
PLpgSQL_stmt_dynfors *new; PLpgSQL_stmt_dynfors *new;
PLpgSQL_expr *expr; PLpgSQL_expr *expr;
int term; int term;
...@@ -942,6 +938,47 @@ for_control : ...@@ -942,6 +938,47 @@ for_control :
$$ = (PLpgSQL_stmt *) new; $$ = (PLpgSQL_stmt *) new;
} }
else if (tok == T_SCALAR &&
yylval.scalar->dtype == PLPGSQL_DTYPE_VAR &&
((PLpgSQL_var *) yylval.scalar)->datatype->typoid == REFCURSOROID)
{
/* It's FOR var IN cursor */
PLpgSQL_stmt_forc *new;
PLpgSQL_var *cursor = (PLpgSQL_var *) yylval.scalar;
char *varname;
new = (PLpgSQL_stmt_forc *) palloc0(sizeof(PLpgSQL_stmt_forc));
new->cmd_type = PLPGSQL_STMT_FORC;
new->lineno = $1;
new->curvar = cursor->varno;
/* Should have had a single variable name */
plpgsql_error_lineno = $2.lineno;
if ($2.scalar && $2.row)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("cursor FOR loop must have just one target variable")));
/* create loop's private RECORD variable */
plpgsql_convert_ident($2.name, &varname, 1);
new->rec = plpgsql_build_record(varname,
$2.lineno,
true);
/* can't use an unbound cursor this way */
if (cursor->cursor_explicit_expr == NULL)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("cursor FOR loop must use a bound cursor variable")));
/* collect cursor's parameters if any */
new->argquery = read_cursor_args(cursor,
K_LOOP,
"LOOP");
$$ = (PLpgSQL_stmt *) new;
}
else else
{ {
PLpgSQL_expr *expr1; PLpgSQL_expr *expr1;
...@@ -1412,81 +1449,8 @@ stmt_open : K_OPEN lno cursor_variable ...@@ -1412,81 +1449,8 @@ stmt_open : K_OPEN lno cursor_variable
} }
else else
{ {
if ($3->cursor_explicit_argrow >= 0) /* predefined cursor query, so read args */
{ new->argquery = read_cursor_args($3, ';', ";");
char *cp;
tok = yylex();
if (tok != '(')
{
plpgsql_error_lineno = plpgsql_scanner_lineno();
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("cursor \"%s\" has arguments",
$3->refname)));
}
/*
* Push back the '(', else read_sql_stmt
* will complain about unbalanced parens.
*/
plpgsql_push_back_token(tok);
new->argquery = read_sql_stmt("SELECT ");
/*
* Now remove the leading and trailing parens,
* because we want "select 1, 2", not
* "select (1, 2)".
*/
cp = new->argquery->query;
if (strncmp(cp, "SELECT", 6) != 0)
{
plpgsql_error_lineno = plpgsql_scanner_lineno();
/* internal error */
elog(ERROR, "expected \"SELECT (\", got \"%s\"",
new->argquery->query);
}
cp += 6;
while (*cp == ' ') /* could be more than 1 space here */
cp++;
if (*cp != '(')
{
plpgsql_error_lineno = plpgsql_scanner_lineno();
/* internal error */
elog(ERROR, "expected \"SELECT (\", got \"%s\"",
new->argquery->query);
}
*cp = ' ';
cp += strlen(cp) - 1;
if (*cp != ')')
yyerror("expected \")\"");
*cp = '\0';
}
else
{
tok = yylex();
if (tok == '(')
{
plpgsql_error_lineno = plpgsql_scanner_lineno();
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("cursor \"%s\" has no arguments",
$3->refname)));
}
if (tok != ';')
{
plpgsql_error_lineno = plpgsql_scanner_lineno();
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("syntax error at \"%s\"",
yytext)));
}
}
} }
$$ = (PLpgSQL_stmt *)new; $$ = (PLpgSQL_stmt *)new;
...@@ -2578,6 +2542,97 @@ check_labels(const char *start_label, const char *end_label) ...@@ -2578,6 +2542,97 @@ check_labels(const char *start_label, const char *end_label)
} }
} }
/*
* Read the arguments (if any) for a cursor, followed by the until token
*
* If cursor has no args, just swallow the until token and return NULL.
* If it does have args, we expect to see "( expr [, expr ...] )" followed
* by the until token. Consume all that and return a SELECT query that
* evaluates the expression(s) (without the outer parens).
*/
static PLpgSQL_expr *
read_cursor_args(PLpgSQL_var *cursor, int until, const char *expected)
{
PLpgSQL_expr *expr;
int tok;
char *cp;
tok = yylex();
if (cursor->cursor_explicit_argrow < 0)
{
/* No arguments expected */
if (tok == '(')
{
plpgsql_error_lineno = plpgsql_scanner_lineno();
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("cursor \"%s\" has no arguments",
cursor->refname)));
}
if (tok != until)
{
plpgsql_error_lineno = plpgsql_scanner_lineno();
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("syntax error at \"%s\"",
yytext)));
}
return NULL;
}
/* Else better provide arguments */
if (tok != '(')
{
plpgsql_error_lineno = plpgsql_scanner_lineno();
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("cursor \"%s\" has arguments",
cursor->refname)));
}
/*
* Push back the '(', else plpgsql_read_expression
* will complain about unbalanced parens.
*/
plpgsql_push_back_token(tok);
expr = plpgsql_read_expression(until, expected);
/*
* Now remove the leading and trailing parens,
* because we want "SELECT 1, 2", not "SELECT (1, 2)".
*/
cp = expr->query;
if (strncmp(cp, "SELECT", 6) != 0)
{
plpgsql_error_lineno = plpgsql_scanner_lineno();
/* internal error */
elog(ERROR, "expected \"SELECT (\", got \"%s\"", expr->query);
}
cp += 6;
while (*cp == ' ') /* could be more than 1 space here */
cp++;
if (*cp != '(')
{
plpgsql_error_lineno = plpgsql_scanner_lineno();
/* internal error */
elog(ERROR, "expected \"SELECT (\", got \"%s\"", expr->query);
}
*cp = ' ';
cp += strlen(cp) - 1;
if (*cp != ')')
yyerror("expected \")\"");
*cp = '\0';
return expr;
}
/* Needed to avoid conflict between different prefix settings: */ /* Needed to avoid conflict between different prefix settings: */
#undef yylex #undef yylex
......
src/pl/plpgsql/src/pl_comp.c
View file @ 347dd6a1
...@@ -8,7 +8,7 @@ ...@@ -8,7 +8,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $PostgreSQL: pgsql/src/pl/plpgsql/src/pl_comp.c,v 1.123 2008/03/27 03:57:34 tgl Exp $ * $PostgreSQL: pgsql/src/pl/plpgsql/src/pl_comp.c,v 1.124 2008/04/06 23:43:29 tgl Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
...@@ -575,25 +575,11 @@ do_compile(FunctionCallInfo fcinfo, ...@@ -575,25 +575,11 @@ do_compile(FunctionCallInfo fcinfo,
errhint("You probably want to use TG_NARGS and TG_ARGV instead."))); errhint("You probably want to use TG_NARGS and TG_ARGV instead.")));
/* Add the record for referencing NEW */ /* Add the record for referencing NEW */
rec = palloc0(sizeof(PLpgSQL_rec)); rec = plpgsql_build_record("new", 0, true);
rec->dtype = PLPGSQL_DTYPE_REC;
rec->refname = pstrdup("new");
rec->tup = NULL;
rec->tupdesc = NULL;
rec->freetup = false;
plpgsql_adddatum((PLpgSQL_datum *) rec);
plpgsql_ns_additem(PLPGSQL_NSTYPE_REC, rec->recno, rec->refname);
function->new_varno = rec->recno; function->new_varno = rec->recno;
/* Add the record for referencing OLD */ /* Add the record for referencing OLD */
rec = palloc0(sizeof(PLpgSQL_rec)); rec = plpgsql_build_record("old", 0, true);
rec->dtype = PLPGSQL_DTYPE_REC;
rec->refname = pstrdup("old");
rec->tup = NULL;
rec->tupdesc = NULL;
rec->freetup = false;
plpgsql_adddatum((PLpgSQL_datum *) rec);
plpgsql_ns_additem(PLPGSQL_NSTYPE_REC, rec->recno, rec->refname);
function->old_varno = rec->recno; function->old_varno = rec->recno;
/* Add the variable tg_name */ /* Add the variable tg_name */
...@@ -1481,21 +1467,10 @@ plpgsql_build_variable(const char *refname, int lineno, PLpgSQL_type *dtype, ...@@ -1481,21 +1467,10 @@ plpgsql_build_variable(const char *refname, int lineno, PLpgSQL_type *dtype,
} }
case PLPGSQL_TTYPE_REC: case PLPGSQL_TTYPE_REC:
{ {
/* /* "record" type -- build a record variable */
* "record" type -- build a variable-contents record variable
*/
PLpgSQL_rec *rec; PLpgSQL_rec *rec;
rec = palloc0(sizeof(PLpgSQL_rec)); rec = plpgsql_build_record(refname, lineno, add2namespace);
rec->dtype = PLPGSQL_DTYPE_REC;
rec->refname = pstrdup(refname);
rec->lineno = lineno;
plpgsql_adddatum((PLpgSQL_datum *) rec);
if (add2namespace)
plpgsql_ns_additem(PLPGSQL_NSTYPE_REC,
rec->recno,
refname);
result = (PLpgSQL_variable *) rec; result = (PLpgSQL_variable *) rec;
break; break;
} }
...@@ -1515,6 +1490,28 @@ plpgsql_build_variable(const char *refname, int lineno, PLpgSQL_type *dtype, ...@@ -1515,6 +1490,28 @@ plpgsql_build_variable(const char *refname, int lineno, PLpgSQL_type *dtype,
return result; return result;
} }
/*
* Build empty named record variable, and optionally add it to namespace
*/
PLpgSQL_rec *
plpgsql_build_record(const char *refname, int lineno, bool add2namespace)
{
PLpgSQL_rec *rec;
rec = palloc0(sizeof(PLpgSQL_rec));
rec->dtype = PLPGSQL_DTYPE_REC;
rec->refname = pstrdup(refname);
rec->lineno = lineno;
rec->tup = NULL;
rec->tupdesc = NULL;
rec->freetup = false;
plpgsql_adddatum((PLpgSQL_datum *) rec);
if (add2namespace)
plpgsql_ns_additem(PLPGSQL_NSTYPE_REC, rec->recno, rec->refname);
return rec;
}
/* /*
* Build a row-variable data structure given the pg_class OID. * Build a row-variable data structure given the pg_class OID.
*/ */
......
src/pl/plpgsql/src/pl_exec.c
View file @ 347dd6a1
This diff is collapsed.
src/pl/plpgsql/src/pl_funcs.c
View file @ 347dd6a1
...@@ -8,7 +8,7 @@ ...@@ -8,7 +8,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $PostgreSQL: pgsql/src/pl/plpgsql/src/pl_funcs.c,v 1.68 2008/04/01 03:51:09 tgl Exp $ * $PostgreSQL: pgsql/src/pl/plpgsql/src/pl_funcs.c,v 1.69 2008/04/06 23:43:29 tgl Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
...@@ -482,6 +482,8 @@ plpgsql_stmt_typename(PLpgSQL_stmt *stmt) ...@@ -482,6 +482,8 @@ plpgsql_stmt_typename(PLpgSQL_stmt *stmt)
return _("FOR with integer loop variable"); return _("FOR with integer loop variable");
case PLPGSQL_STMT_FORS: case PLPGSQL_STMT_FORS:
return _("FOR over SELECT rows"); return _("FOR over SELECT rows");
case PLPGSQL_STMT_FORC:
return _("FOR over cursor");
case PLPGSQL_STMT_EXIT: case PLPGSQL_STMT_EXIT:
return "EXIT"; return "EXIT";
case PLPGSQL_STMT_RETURN: case PLPGSQL_STMT_RETURN:
...@@ -528,6 +530,7 @@ static void dump_loop(PLpgSQL_stmt_loop *stmt); ...@@ -528,6 +530,7 @@ static void dump_loop(PLpgSQL_stmt_loop *stmt);
static void dump_while(PLpgSQL_stmt_while *stmt); static void dump_while(PLpgSQL_stmt_while *stmt);
static void dump_fori(PLpgSQL_stmt_fori *stmt); static void dump_fori(PLpgSQL_stmt_fori *stmt);
static void dump_fors(PLpgSQL_stmt_fors *stmt); static void dump_fors(PLpgSQL_stmt_fors *stmt);
static void dump_forc(PLpgSQL_stmt_forc *stmt);
static void dump_exit(PLpgSQL_stmt_exit *stmt); static void dump_exit(PLpgSQL_stmt_exit *stmt);
static void dump_return(PLpgSQL_stmt_return *stmt); static void dump_return(PLpgSQL_stmt_return *stmt);
static void dump_return_next(PLpgSQL_stmt_return_next *stmt); static void dump_return_next(PLpgSQL_stmt_return_next *stmt);
...@@ -581,6 +584,9 @@ dump_stmt(PLpgSQL_stmt *stmt) ...@@ -581,6 +584,9 @@ dump_stmt(PLpgSQL_stmt *stmt)
case PLPGSQL_STMT_FORS: case PLPGSQL_STMT_FORS:
dump_fors((PLpgSQL_stmt_fors *) stmt); dump_fors((PLpgSQL_stmt_fors *) stmt);
break; break;
case PLPGSQL_STMT_FORC:
dump_forc((PLpgSQL_stmt_forc *) stmt);
break;
case PLPGSQL_STMT_EXIT: case PLPGSQL_STMT_EXIT:
dump_exit((PLpgSQL_stmt_exit *) stmt); dump_exit((PLpgSQL_stmt_exit *) stmt);
break; break;
...@@ -775,6 +781,29 @@ dump_fors(PLpgSQL_stmt_fors *stmt) ...@@ -775,6 +781,29 @@ dump_fors(PLpgSQL_stmt_fors *stmt)
printf(" ENDFORS\n"); printf(" ENDFORS\n");
} }
static void
dump_forc(PLpgSQL_stmt_forc *stmt)
{
dump_ind();
printf("FORC %s ", stmt->rec->refname);
printf("curvar=%d\n", stmt->curvar);
dump_indent += 2;
if (stmt->argquery != NULL)
{
dump_ind();
printf(" arguments = ");
dump_expr(stmt->argquery);
printf("\n");
}
dump_indent -= 2;
dump_stmts(stmt->body);
dump_ind();
printf(" ENDFORC\n");
}
static void static void
dump_open(PLpgSQL_stmt_open *stmt) dump_open(PLpgSQL_stmt_open *stmt)
{ {
......
src/pl/plpgsql/src/plpgsql.h
View file @ 347dd6a1
...@@ -8,7 +8,7 @@ ...@@ -8,7 +8,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $PostgreSQL: pgsql/src/pl/plpgsql/src/plpgsql.h,v 1.96 2008/04/01 03:51:09 tgl Exp $ * $PostgreSQL: pgsql/src/pl/plpgsql/src/plpgsql.h,v 1.97 2008/04/06 23:43:29 tgl Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
...@@ -80,6 +80,7 @@ enum ...@@ -80,6 +80,7 @@ enum
PLPGSQL_STMT_WHILE, PLPGSQL_STMT_WHILE,
PLPGSQL_STMT_FORI, PLPGSQL_STMT_FORI,
PLPGSQL_STMT_FORS, PLPGSQL_STMT_FORS,
PLPGSQL_STMT_FORC,
PLPGSQL_STMT_EXIT, PLPGSQL_STMT_EXIT,
PLPGSQL_STMT_RETURN, PLPGSQL_STMT_RETURN,
PLPGSQL_STMT_RETURN_NEXT, PLPGSQL_STMT_RETURN_NEXT,
...@@ -409,6 +410,21 @@ typedef struct ...@@ -409,6 +410,21 @@ typedef struct
} PLpgSQL_stmt_fori; } PLpgSQL_stmt_fori;
/*
* PLpgSQL_stmt_forq represents a FOR statement running over a SQL query.
* It is the common supertype of PLpgSQL_stmt_fors, PLpgSQL_stmt_forc
* and PLpgSQL_dynfors.
*/
typedef struct
{
int cmd_type;
int lineno;
char *label;
PLpgSQL_rec *rec;
PLpgSQL_row *row;
List *body; /* List of statements */
} PLpgSQL_stmt_forq;
typedef struct typedef struct
{ /* FOR statement running over SELECT */ { /* FOR statement running over SELECT */
int cmd_type; int cmd_type;
...@@ -416,10 +432,23 @@ typedef struct ...@@ -416,10 +432,23 @@ typedef struct
char *label; char *label;
PLpgSQL_rec *rec; PLpgSQL_rec *rec;
PLpgSQL_row *row; PLpgSQL_row *row;
PLpgSQL_expr *query;
List *body; /* List of statements */ List *body; /* List of statements */
/* end of fields that must match PLpgSQL_stmt_forq */
PLpgSQL_expr *query;
} PLpgSQL_stmt_fors; } PLpgSQL_stmt_fors;
typedef struct
{ /* FOR statement running over cursor */
int cmd_type;
int lineno;
char *label;
PLpgSQL_rec *rec;
PLpgSQL_row *row;
List *body; /* List of statements */
/* end of fields that must match PLpgSQL_stmt_forq */
int curvar;
PLpgSQL_expr *argquery; /* cursor arguments if any */
} PLpgSQL_stmt_forc;
typedef struct typedef struct
{ /* FOR statement running over EXECUTE */ { /* FOR statement running over EXECUTE */
...@@ -428,8 +457,9 @@ typedef struct ...@@ -428,8 +457,9 @@ typedef struct
char *label; char *label;
PLpgSQL_rec *rec; PLpgSQL_rec *rec;
PLpgSQL_row *row; PLpgSQL_row *row;
PLpgSQL_expr *query;
List *body; /* List of statements */ List *body; /* List of statements */
/* end of fields that must match PLpgSQL_stmt_forq */
PLpgSQL_expr *query;
List *params; /* USING expressions */ List *params; /* USING expressions */
} PLpgSQL_stmt_dynfors; } PLpgSQL_stmt_dynfors;
...@@ -738,6 +768,8 @@ extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod); ...@@ -738,6 +768,8 @@ extern PLpgSQL_type *plpgsql_build_datatype(Oid typeOid, int32 typmod);
extern PLpgSQL_variable *plpgsql_build_variable(const char *refname, int lineno, extern PLpgSQL_variable *plpgsql_build_variable(const char *refname, int lineno,
PLpgSQL_type *dtype, PLpgSQL_type *dtype,
bool add2namespace); bool add2namespace);
extern PLpgSQL_rec *plpgsql_build_record(const char *refname, int lineno,
bool add2namespace);
extern PLpgSQL_condition *plpgsql_parse_err_condition(char *condname); extern PLpgSQL_condition *plpgsql_parse_err_condition(char *condname);
extern void plpgsql_adddatum(PLpgSQL_datum *new); extern void plpgsql_adddatum(PLpgSQL_datum *new);
extern int plpgsql_add_initdatums(int **varnos); extern int plpgsql_add_initdatums(int **varnos);
......
src/test/regress/expected/plpgsql.out
View file @ 347dd6a1
...@@ -3151,3 +3151,119 @@ NOTICE: 6 ...@@ -3151,3 +3151,119 @@ NOTICE: 6
26 26
(1 row) (1 row)
-- test FOR-over-cursor
create or replace function forc01() returns void as $$
declare
c cursor(r1 integer, r2 integer)
for select * from generate_series(r1,r2) i;
c2 cursor
for select * from generate_series(41,43) i;
begin
for r in c(5,7) loop
raise notice '% from %', r.i, c;
end loop;
-- again, to test if cursor was closed properly
for r in c(9,10) loop
raise notice '% from %', r.i, c;
end loop;
-- and test a parameterless cursor
for r in c2 loop
raise notice '% from %', r.i, c2;
end loop;
-- and try it with a hand-assigned name
raise notice 'after loop, c2 = %', c2;
c2 := 'special_name';
for r in c2 loop
raise notice '% from %', r.i, c2;
end loop;
raise notice 'after loop, c2 = %', c2;
-- and try it with a generated name
-- (which we can't show in the output because it's variable)
c2 := null;
for r in c2 loop
raise notice '%', r.i;
end loop;
raise notice 'after loop, c2 = %', c2;
return;
end;
$$ language plpgsql;
select forc01();
NOTICE: 5 from c
NOTICE: 6 from c
NOTICE: 7 from c
NOTICE: 9 from c
NOTICE: 10 from c
NOTICE: 41 from c2
NOTICE: 42 from c2
NOTICE: 43 from c2
NOTICE: after loop, c2 = c2
NOTICE: 41 from special_name
NOTICE: 42 from special_name
NOTICE: 43 from special_name
NOTICE: after loop, c2 = special_name
NOTICE: 41
NOTICE: 42
NOTICE: 43
NOTICE: after loop, c2 = <NULL>
forc01
--------
(1 row)
-- try updating the cursor's current row
create temp table forc_test as
select n as i, n as j from generate_series(1,10) n;
create or replace function forc01() returns void as $$
declare
c cursor for select * from forc_test;
begin
for r in c loop
raise notice '%, %', r.i, r.j;
update forc_test set i = i * 100, j = r.j * 2 where current of c;
end loop;
end;
$$ language plpgsql;
select forc01();
NOTICE: 1, 1
NOTICE: 2, 2
NOTICE: 3, 3
NOTICE: 4, 4
NOTICE: 5, 5
NOTICE: 6, 6
NOTICE: 7, 7
NOTICE: 8, 8
NOTICE: 9, 9
NOTICE: 10, 10
forc01
--------
(1 row)
select * from forc_test;
i | j
------+----
100 | 2
200 | 4
300 | 6
400 | 8
500 | 10
600 | 12
700 | 14
800 | 16
900 | 18
1000 | 20
(10 rows)
drop function forc01();
-- fail because cursor has no query bound to it
create or replace function forc_bad() returns void as $$
declare
c refcursor;
begin
for r in c loop
raise notice '%', r.i;
end loop;
end;
$$ language plpgsql;
ERROR: cursor FOR loop must use a bound cursor variable
CONTEXT: compile of PL/pgSQL function "forc_bad" near line 4
src/test/regress/sql/plpgsql.sql
View file @ 347dd6a1
...@@ -2595,3 +2595,77 @@ end ...@@ -2595,3 +2595,77 @@ end
$$ language plpgsql; $$ language plpgsql;
select exc_using(5, 'foobar'); select exc_using(5, 'foobar');
-- test FOR-over-cursor
create or replace function forc01() returns void as $$
declare
c cursor(r1 integer, r2 integer)
for select * from generate_series(r1,r2) i;
c2 cursor
for select * from generate_series(41,43) i;
begin
for r in c(5,7) loop
raise notice '% from %', r.i, c;
end loop;
-- again, to test if cursor was closed properly
for r in c(9,10) loop
raise notice '% from %', r.i, c;
end loop;
-- and test a parameterless cursor
for r in c2 loop
raise notice '% from %', r.i, c2;
end loop;
-- and try it with a hand-assigned name
raise notice 'after loop, c2 = %', c2;
c2 := 'special_name';
for r in c2 loop
raise notice '% from %', r.i, c2;
end loop;
raise notice 'after loop, c2 = %', c2;
-- and try it with a generated name
-- (which we can't show in the output because it's variable)
c2 := null;
for r in c2 loop
raise notice '%', r.i;
end loop;
raise notice 'after loop, c2 = %', c2;
return;
end;
$$ language plpgsql;
select forc01();
-- try updating the cursor's current row
create temp table forc_test as
select n as i, n as j from generate_series(1,10) n;
create or replace function forc01() returns void as $$
declare
c cursor for select * from forc_test;
begin
for r in c loop
raise notice '%, %', r.i, r.j;
update forc_test set i = i * 100, j = r.j * 2 where current of c;
end loop;
end;
$$ language plpgsql;
select forc01();
select * from forc_test;
drop function forc01();
-- fail because cursor has no query bound to it
create or replace function forc_bad() returns void as $$
declare
c refcursor;
begin
for r in c loop
raise notice '%', r.i;
end loop;
end;
$$ language plpgsql;
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