mirror of https://github.com/postgres/postgres
Allow the types of parameters to PREPARE to be inferred. If a parameter's
data type is unspecified or is declared to be "unknown", the type will be inferred from the context in which the parameter is used. This was already possible for protocol-level prepared statements.
This commit is contained in:
Neil Conway
parent
f7ea931287
commit
106a3695f5
|
|
@ -1,5 +1,5 @@
|
|||
<!--
|
||||
$PostgreSQL: pgsql/doc/src/sgml/ref/deallocate.sgml,v 1.7 2004/09/30 04:23:27 neilc Exp $
|
||||
$PostgreSQL: pgsql/doc/src/sgml/ref/deallocate.sgml,v 1.8 2006/01/15 22:18:46 neilc Exp $
|
||||
PostgreSQL documentation
|
||||
-->
|
||||
|
||||
|
|
@ -25,7 +25,7 @@ PostgreSQL documentation
|
|||
|
||||
<refsynopsisdiv>
|
||||
<synopsis>
|
||||
DEALLOCATE [ PREPARE ] <replaceable class="parameter">plan_name</replaceable>
|
||||
DEALLOCATE [ PREPARE ] <replaceable class="parameter">name</replaceable>
|
||||
</synopsis>
|
||||
</refsynopsisdiv>
|
||||
|
||||
|
|
@ -58,7 +58,7 @@ DEALLOCATE [ PREPARE ] <replaceable class="parameter">plan_name</replaceable>
|
|||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term><replaceable class="parameter">plan_name</replaceable></term>
|
||||
<term><replaceable class="parameter">name</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
The name of the prepared statement to deallocate.
|
||||
|
|
|
|||
|
|
@ -1,5 +1,5 @@
|
|||
<!--
|
||||
$PostgreSQL: pgsql/doc/src/sgml/ref/execute.sgml,v 1.12 2004/09/30 04:23:27 neilc Exp $
|
||||
$PostgreSQL: pgsql/doc/src/sgml/ref/execute.sgml,v 1.13 2006/01/15 22:18:46 neilc Exp $
|
||||
PostgreSQL documentation
|
||||
-->
|
||||
|
||||
|
|
@ -25,7 +25,7 @@ PostgreSQL documentation
|
|||
|
||||
<refsynopsisdiv>
|
||||
<synopsis>
|
||||
EXECUTE <replaceable class="PARAMETER">plan_name</replaceable> [ (<replaceable class="PARAMETER">parameter</replaceable> [, ...] ) ]
|
||||
EXECUTE <replaceable class="PARAMETER">name</replaceable> [ (<replaceable class="PARAMETER">parameter</replaceable> [, ...] ) ]
|
||||
</synopsis>
|
||||
</refsynopsisdiv>
|
||||
|
||||
|
|
@ -60,7 +60,7 @@ EXECUTE <replaceable class="PARAMETER">plan_name</replaceable> [ (<replaceable c
|
|||
|
||||
<variablelist>
|
||||
<varlistentry>
|
||||
<term><replaceable class="PARAMETER">plan_name</replaceable></term>
|
||||
<term><replaceable class="PARAMETER">name</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
The name of the prepared statement to execute.
|
||||
|
|
@ -73,10 +73,9 @@ EXECUTE <replaceable class="PARAMETER">plan_name</replaceable> [ (<replaceable c
|
|||
<listitem>
|
||||
<para>
|
||||
The actual value of a parameter to the prepared statement. This
|
||||
must be an expression yielding a value of a type compatible with
|
||||
the data type specified for this parameter position in the
|
||||
<command>PREPARE</command> command that created the prepared
|
||||
statement.
|
||||
must be an expression yielding a value that is compatible with
|
||||
the data type of this parameter, as was determined when the
|
||||
prepared statement was created.
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
|
|
|||
|
|
@ -1,5 +1,5 @@
|
|||
<!--
|
||||
$PostgreSQL: pgsql/doc/src/sgml/ref/prepare.sgml,v 1.17 2006/01/08 07:00:25 neilc Exp $
|
||||
$PostgreSQL: pgsql/doc/src/sgml/ref/prepare.sgml,v 1.18 2006/01/15 22:18:46 neilc Exp $
|
||||
PostgreSQL documentation
|
||||
-->
|
||||
|
||||
|
|
@ -25,7 +25,7 @@ PostgreSQL documentation
|
|||
|
||||
<refsynopsisdiv>
|
||||
<synopsis>
|
||||
PREPARE <replaceable class="PARAMETER">plan_name</replaceable> [ (<replaceable class="PARAMETER">datatype</replaceable> [, ...] ) ] AS <replaceable class="PARAMETER">statement</replaceable>
|
||||
PREPARE <replaceable class="PARAMETER">name</replaceable> [ (<replaceable class="PARAMETER">datatype</replaceable> [, ...] ) ] AS <replaceable class="PARAMETER">statement</replaceable>
|
||||
</synopsis>
|
||||
</refsynopsisdiv>
|
||||
|
||||
|
|
@ -45,13 +45,15 @@ PREPARE <replaceable class="PARAMETER">plan_name</replaceable> [ (<replaceable c
|
|||
|
||||
<para>
|
||||
Prepared statements can take parameters: values that are
|
||||
substituted into the statement when it is executed. To include
|
||||
parameters in a prepared statement, supply a list of data types in
|
||||
the <command>PREPARE</command> statement, and, in the statement to
|
||||
be prepared itself, refer to the parameters by position using
|
||||
<literal>$1</literal>, <literal>$2</literal>, etc. When executing
|
||||
the statement, specify the actual values for these parameters in
|
||||
the <command>EXECUTE</command> statement. Refer to <xref
|
||||
substituted into the statement when it is executed. When creating
|
||||
the prepared statement, refer to parameters by position, using
|
||||
<literal>$1</>, <literal>$2</>, etc. A corresponding list of
|
||||
parameter data types can optionally be specified. When a
|
||||
parameter's data type is not specified or is declared as
|
||||
<literal>unknown</literal>, the type is inferred from the context
|
||||
in which the parameter is used (if possible). When executing the
|
||||
statement, specify the actual values for these parameters in the
|
||||
<command>EXECUTE</command> statement. Refer to <xref
|
||||
linkend="sql-execute" endterm="sql-execute-title"> for more
|
||||
information about that.
|
||||
</para>
|
||||
|
|
@ -84,7 +86,7 @@ PREPARE <replaceable class="PARAMETER">plan_name</replaceable> [ (<replaceable c
|
|||
|
||||
<variablelist>
|
||||
<varlistentry>
|
||||
<term><replaceable class="PARAMETER">plan_name</replaceable></term>
|
||||
<term><replaceable class="PARAMETER">name</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
An arbitrary name given to this particular prepared
|
||||
|
|
@ -99,8 +101,11 @@ PREPARE <replaceable class="PARAMETER">plan_name</replaceable> [ (<replaceable c
|
|||
<term><replaceable class="PARAMETER">datatype</replaceable></term>
|
||||
<listitem>
|
||||
<para>
|
||||
The data type of a parameter to the prepared statement. To
|
||||
refer to the parameters in the prepared statement itself, use
|
||||
The data type of a parameter to the prepared statement. If the
|
||||
data type of a particular parameter is unspecified or is
|
||||
specified as <literal>unknown</literal>, it will be inferred
|
||||
from the context in which the parameter is used. To refer to the
|
||||
parameters in the prepared statement itself, use
|
||||
<literal>$1</literal>, <literal>$2</literal>, etc.
|
||||
</para>
|
||||
</listitem>
|
||||
|
|
@ -155,8 +160,8 @@ PREPARE <replaceable class="PARAMETER">plan_name</replaceable> [ (<replaceable c
|
|||
<refsect1 id="sql-prepare-examples">
|
||||
<title id="sql-prepare-examples-title">Examples</title>
|
||||
<para>
|
||||
Create a prepared query for an <command>INSERT</command> statement,
|
||||
and then execute it:
|
||||
Create a prepared statement for an <command>INSERT</command>
|
||||
statement, and then execute it:
|
||||
<programlisting>
|
||||
PREPARE fooplan (int, text, bool, numeric) AS
|
||||
INSERT INTO foo VALUES($1, $2, $3, $4);
|
||||
|
|
@ -165,14 +170,17 @@ EXECUTE fooplan(1, 'Hunter Valley', 't', 200.00);
|
|||
</para>
|
||||
|
||||
<para>
|
||||
Create a prepared query for a <command>SELECT</command> statement,
|
||||
and then execute it:
|
||||
Create a prepared statement for a <command>SELECT</command>
|
||||
statement, and then execute it:
|
||||
<programlisting>
|
||||
PREPARE usrrptplan (int, date) AS
|
||||
PREPARE usrrptplan (int) AS
|
||||
SELECT * FROM users u, logs l WHERE u.usrid=$1 AND u.usrid=l.usrid
|
||||
AND l.date = $2;
|
||||
EXECUTE usrrptplan(1, current_date);
|
||||
</programlisting>
|
||||
|
||||
Note that the data type of the second parameter is not specified,
|
||||
so it is inferred from the context in which <literal>$2</> is used.
|
||||
</para>
|
||||
</refsect1>
|
||||
<refsect1>
|
||||
|
|
|
|||
|
|
@ -6,7 +6,7 @@
|
|||
* Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.327 2005/11/22 18:17:15 momjian Exp $
|
||||
* $PostgreSQL: pgsql/src/backend/parser/analyze.c,v 1.328 2006/01/15 22:18:46 neilc Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
|
|
@ -2584,10 +2584,11 @@ static Query *
|
|||
transformPrepareStmt(ParseState *pstate, PrepareStmt *stmt)
|
||||
{
|
||||
Query *result = makeNode(Query);
|
||||
List *argtype_oids = NIL; /* argtype OIDs in a list */
|
||||
List *argtype_oids; /* argtype OIDs in a list */
|
||||
Oid *argtoids = NULL; /* and as an array */
|
||||
int nargs;
|
||||
List *queries;
|
||||
int i;
|
||||
|
||||
result->commandType = CMD_UTILITY;
|
||||
result->utilityStmt = (Node *) stmt;
|
||||
|
|
@ -2598,27 +2599,27 @@ transformPrepareStmt(ParseState *pstate, PrepareStmt *stmt)
|
|||
if (nargs)
|
||||
{
|
||||
ListCell *l;
|
||||
int i = 0;
|
||||
|
||||
argtoids = (Oid *) palloc(nargs * sizeof(Oid));
|
||||
i = 0;
|
||||
|
||||
foreach(l, stmt->argtypes)
|
||||
{
|
||||
TypeName *tn = lfirst(l);
|
||||
Oid toid = typenameTypeId(tn);
|
||||
|
||||
argtype_oids = lappend_oid(argtype_oids, toid);
|
||||
argtoids[i++] = toid;
|
||||
}
|
||||
}
|
||||
|
||||
stmt->argtype_oids = argtype_oids;
|
||||
|
||||
/*
|
||||
* Analyze the statement using these parameter types (any parameters
|
||||
* passed in from above us will not be visible to it).
|
||||
* Analyze the statement using these parameter types (any
|
||||
* parameters passed in from above us will not be visible to it),
|
||||
* allowing information about unknown parameters to be deduced
|
||||
* from context.
|
||||
*/
|
||||
queries = parse_analyze((Node *) stmt->query, argtoids, nargs);
|
||||
queries = parse_analyze_varparams((Node *) stmt->query,
|
||||
&argtoids, &nargs);
|
||||
|
||||
/*
|
||||
* Shouldn't get any extra statements, since grammar only allows
|
||||
|
|
@ -2627,8 +2628,26 @@ transformPrepareStmt(ParseState *pstate, PrepareStmt *stmt)
|
|||
if (list_length(queries) != 1)
|
||||
elog(ERROR, "unexpected extra stuff in prepared statement");
|
||||
|
||||
stmt->query = linitial(queries);
|
||||
/*
|
||||
* Check that all parameter types were determined, and convert the
|
||||
* array of OIDs into a list for storage.
|
||||
*/
|
||||
argtype_oids = NIL;
|
||||
for (i = 0; i < nargs; i++)
|
||||
{
|
||||
Oid argtype = argtoids[i];
|
||||
|
||||
if (argtype == InvalidOid || argtype == UNKNOWNOID)
|
||||
ereport(ERROR,
|
||||
(errcode(ERRCODE_INDETERMINATE_DATATYPE),
|
||||
errmsg("could not determine data type of parameter $%d",
|
||||
i + 1)));
|
||||
|
||||
argtype_oids = lappend_oid(argtype_oids, argtype);
|
||||
}
|
||||
|
||||
stmt->argtype_oids = argtype_oids;
|
||||
stmt->query = linitial(queries);
|
||||
return result;
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -58,14 +58,6 @@ SELECT name, statement, parameter_types FROM pg_prepared_statements;
|
|||
PREPARE q2(text) AS
|
||||
SELECT datname, datistemplate, datallowconn
|
||||
FROM pg_database WHERE datname = $1;
|
||||
SELECT name, statement, parameter_types FROM pg_prepared_statements;
|
||||
name | statement | parameter_types
|
||||
------+--------------------------------------------------------------------------------------------------------+-----------------
|
||||
q2 | PREPARE q2(text) AS
|
||||
SELECT datname, datistemplate, datallowconn
|
||||
FROM pg_database WHERE datname = $1; | {25}
|
||||
(1 row)
|
||||
|
||||
EXECUTE q2('regression');
|
||||
datname | datistemplate | datallowconn
|
||||
------------+---------------+--------------
|
||||
|
|
@ -75,17 +67,6 @@ EXECUTE q2('regression');
|
|||
PREPARE q3(text, int, float, boolean, oid, smallint) AS
|
||||
SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR
|
||||
ten = $3::bigint OR true = $4 OR oid = $5 OR odd = $6::int);
|
||||
SELECT name, statement, parameter_types FROM pg_prepared_statements;
|
||||
name | statement | parameter_types
|
||||
------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------
|
||||
q2 | PREPARE q2(text) AS
|
||||
SELECT datname, datistemplate, datallowconn
|
||||
FROM pg_database WHERE datname = $1; | {25}
|
||||
q3 | PREPARE q3(text, int, float, boolean, oid, smallint) AS
|
||||
SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR
|
||||
ten = $3::bigint OR true = $4 OR oid = $5 OR odd = $6::int); | {25,23,701,16,26,21}
|
||||
(2 rows)
|
||||
|
||||
EXECUTE q3('AAAAxx', 5::smallint, 10.5::float, false, 500::oid, 4::bigint);
|
||||
unique1 | unique2 | two | four | ten | twenty | hundred | thousand | twothousand | fivethous | tenthous | odd | even | stringu1 | stringu2 | string4
|
||||
---------+---------+-----+------+-----+--------+---------+----------+-------------+-----------+----------+-----+------+----------+----------+---------
|
||||
|
|
@ -160,3 +141,26 @@ SELECT * FROM q5_prep_results;
|
|||
5905 | 9537 | 1 | 1 | 5 | 5 | 5 | 905 | 1905 | 905 | 5905 | 10 | 11 | DTAAAA | VCOAAA | HHHHxx
|
||||
(16 rows)
|
||||
|
||||
-- unknown or unspecified parameter types: should succeed
|
||||
PREPARE q6 AS
|
||||
SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;
|
||||
PREPARE q7(unknown) AS
|
||||
SELECT * FROM road WHERE thepath = $1;
|
||||
SELECT name, statement, parameter_types FROM pg_prepared_statements
|
||||
ORDER BY name;
|
||||
name | statement | parameter_types
|
||||
------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------
|
||||
q2 | PREPARE q2(text) AS
|
||||
SELECT datname, datistemplate, datallowconn
|
||||
FROM pg_database WHERE datname = $1; | {25}
|
||||
q3 | PREPARE q3(text, int, float, boolean, oid, smallint) AS
|
||||
SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR
|
||||
ten = $3::bigint OR true = $4 OR oid = $5 OR odd = $6::int); | {25,23,701,16,26,21}
|
||||
q5 | PREPARE q5(int, text) AS
|
||||
SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2; | {23,25}
|
||||
q6 | PREPARE q6 AS
|
||||
SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2; | {23,19}
|
||||
q7 | PREPARE q7(unknown) AS
|
||||
SELECT * FROM road WHERE thepath = $1; | {602}
|
||||
(5 rows)
|
||||
|
||||
|
|
|
|||
|
|
@ -34,16 +34,12 @@ PREPARE q2(text) AS
|
|||
SELECT datname, datistemplate, datallowconn
|
||||
FROM pg_database WHERE datname = $1;
|
||||
|
||||
SELECT name, statement, parameter_types FROM pg_prepared_statements;
|
||||
|
||||
EXECUTE q2('regression');
|
||||
|
||||
PREPARE q3(text, int, float, boolean, oid, smallint) AS
|
||||
SELECT * FROM tenk1 WHERE string4 = $1 AND (four = $2 OR
|
||||
ten = $3::bigint OR true = $4 OR oid = $5 OR odd = $6::int);
|
||||
|
||||
SELECT name, statement, parameter_types FROM pg_prepared_statements;
|
||||
|
||||
EXECUTE q3('AAAAxx', 5::smallint, 10.5::float, false, 500::oid, 4::bigint);
|
||||
|
||||
-- too few params
|
||||
|
|
@ -63,3 +59,12 @@ PREPARE q5(int, text) AS
|
|||
SELECT * FROM tenk1 WHERE unique1 = $1 OR stringu1 = $2;
|
||||
CREATE TEMPORARY TABLE q5_prep_results AS EXECUTE q5(200, 'DTAAAA');
|
||||
SELECT * FROM q5_prep_results;
|
||||
|
||||
-- unknown or unspecified parameter types: should succeed
|
||||
PREPARE q6 AS
|
||||
SELECT * FROM tenk1 WHERE unique1 = $1 AND stringu1 = $2;
|
||||
PREPARE q7(unknown) AS
|
||||
SELECT * FROM road WHERE thepath = $1;
|
||||
|
||||
SELECT name, statement, parameter_types FROM pg_prepared_statements
|
||||
ORDER BY name;
|
||||
|
|
|
|||
Loading…
Reference in New Issue