8000 Add PQexecPrepared() and PQsendQueryPrepared() functions, to allow · fschopp/postgres@0be731a · GitHub
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Add PQexecPrepared() and PQsendQueryPrepared() functions, to allow< 8000 /div>libpq users to perform Bind/Execute of previously prepared statements. Per yesterday's discussion, this offers enough performance improvement to justify bending the 'no new features during beta' rule.
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‎doc/src/sgml/libpq.sgml

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<!--
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$Header: /cvsroot/pgsql/doc/src/sgml/libpq.sgml,v 1.130 2003/08/01 03:10:04 momjian Exp $
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$Header: /cvsroot/pgsql/doc/src/sgml/libpq.sgml,v 1.131 2003/08/13 16:29:03 tgl Exp $
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-->
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<chapter id="libpq">
@@ -1090,6 +1090,53 @@ than one nonempty command.) This is a limitation of the underlying protocol,
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but has some usefulness as an extra defense against SQL-injection attacks.
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</para>
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<para>
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<variablelist>
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<varlistentry>
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<term><function>PQexecPrepared</function></term>
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<listitem>
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<para>
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Sends a request to execute a prepared statement with given
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parameters, and waits for the result.
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<synopsis>
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PGresult *PQexecPrepared(PGconn *conn,
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const char *stmtName,
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int nParams,
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const char * const *paramValues,
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const int *paramLengths,
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const int *paramFormats,
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int resultFormat);
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</synopsis>
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</para>
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<para>
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<function>PQexecPrepared</> is like <function>PQexecParams</>, but the
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command to be executed is specified by naming a previously-prepared
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statement, instead of giving a query string. This feature allows commands
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that will be used repeatedly to be parsed and planned just once, rather
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than each time they are executed.
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<function>PQexecPrepared</> is supported only in protocol 3.0 and later
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connections; it will fail when using protocol 2.0.
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</para>
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<para>
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The parameters are identical to <function>PQexecParams</>, except that the
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name of a prepared statement is given instead of a query string, and the
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<parameter>paramTypes[]</> parameter is not present (it is not needed since
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the prepared statement's parameter types were determined when it was created).
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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Presently, prepared statements for use with <function>PQexecPrepared</>
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must be set up by executing an SQL <command>PREPARE</> command,
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which is typically sent with <function>PQexec</> (though any of
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<application>libpq</>'s query-submission functions may be used).
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A lower-level interface for preparing statements may be offered in a
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future release.
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</para>
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<para>
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The <structname>PGresult</structname> structure encapsulates the result
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returned by the server.
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<para>
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Note that it is not necessary nor correct to do escaping when a data
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value is passed as a separate parameter in <function>PQexecParams</> or
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<function>PQsendQueryParams</>.
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its sibling routines.
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<synopsis>
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size_t PQescapeString (char *to, const char *from, size_t length);
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Applications that do not like these limitations can instead use the
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underlying functions that <function>PQexec</function> is built from:
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<function>PQsendQuery</function> and <function>PQgetResult</function>.
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There is also <function>PQsendQueryParams</function>, which can be
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used with <function>PQgetResult</function> to duplicate the functionality
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of <function>PQexecParams</function>.
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There are also <function>PQsendQueryParams</function> and
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<function>PQsendQueryPrepared</function>, which can be used with
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<function>PQgetResult</function> to duplicate the functionality of
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<function>PQexecParams</function> and <function>PQexecPrepared</function>
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respectively.
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<variablelist>
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<varlistentry>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><function>PQsendQueryPrepared</function></term>
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<listitem>
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<para>
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Sends a request to execute a prepared statement with given
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parameters, without waiting for the result(s).
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<synopsis>
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int PQsendQueryPrepared(PGconn *conn,
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const char *stmtName,
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int nParams,
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const char * const *paramValues,
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const int *paramLengths,
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const int *paramFormats,
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int resultFormat);
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</synopsis>
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This is similar to <function>PQsendQueryParams</function>, but the
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command to be executed is specified by naming a previously-prepared
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statement, instead of giving a query string.
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The function's parameters are handled identically to
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<function>PQexecPrepared</function>. Like
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<function>PQexecPrepared</function>, it will not work on 2.0-protocol
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connections.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><function>PQgetResult</function></term>
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<listitem>
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<para>
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Waits for the next result from a prior
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<function>PQsendQuery</function> or
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<function>PQsendQueryParams</function>,
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<function>PQsendQuery</function>,
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<function>PQsendQueryParams</function>, or
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<function>PQsendQueryPrepared</function> call,
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and returns it. A null pointer is returned when the command is complete
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and there will be no more results.
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<synopsis>

‎src/interfaces/libpq/blibpqdll.def

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_PQftable @ 107
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_PQftablecol @ 108
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_PQfformat @ 109
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_PQexecPrepared @ 110
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_PQsendQueryPrepared @ 111
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; Aliases for MS compatible names
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PQconnectdb = _PQconnectdb
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PQftable = _PQftable
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PQftablecol = _PQftablecol
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PQfformat = _PQfformat
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PQexecPrepared = _PQexecPrepared
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PQsendQueryPrepared = _PQsendQueryPrepared

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