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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >DECLARE</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REV="MADE" HREF="mailto:pgsql-docs@postgresql.org"><LINK REL="HOME" TITLE="PostgreSQL 9.2.24 Documentation" HREF="index.html"><LINK REL="UP" TITLE="Embedded SQL Commands" HREF="ecpg-sql-commands.html"><LINK REL="PREVIOUS" TITLE="DEALLOCATE DESCRIPTOR" HREF="ecpg-sql-deallocate-descriptor.html"><LINK REL="NEXT" TITLE="DESCRIBE" HREF="ecpg-sql-describe.html"><LINK REL="STYLESHEET" TYPE="text/css" HREF="stylesheet.css"><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"><META NAME="creation" CONTENT="2017-11-06T22:43:11"></HEAD ><BODY CLASS="REFENTRY" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" ><A HREF="index.html" >PostgreSQL 9.2.24 Documentation</A ></TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A TITLE="DEALLOCATE DESCRIPTOR" HREF="ecpg-sql-deallocate-descriptor.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="ecpg-sql-commands.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="20%" ALIGN="right" VALIGN="top" ><A TITLE="DESCRIBE" HREF="ecpg-sql-describe.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="ECPG-SQL-DECLARE" ></A >DECLARE</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN45300" ></A ><H2 >Name</H2 >DECLARE -- define a cursor</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN45303" ></A ><H2 >Synopsis</H2 ><PRE CLASS="SYNOPSIS" >DECLARE <TT CLASS="REPLACEABLE" ><I >cursor_name</I ></TT > [ BINARY ] [ INSENSITIVE ] [ [ NO ] SCROLL ] CURSOR [ { WITH | WITHOUT } HOLD ] FOR <TT CLASS="REPLACEABLE" ><I >prepared_name</I ></TT > DECLARE <TT CLASS="REPLACEABLE" ><I >cursor_name</I ></TT > [ BINARY ] [ INSENSITIVE ] [ [ NO ] SCROLL ] CURSOR [ { WITH | WITHOUT } HOLD ] FOR <TT CLASS="REPLACEABLE" ><I >query</I ></TT ></PRE ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN45309" ></A ><H2 >Description</H2 ><P > <TT CLASS="COMMAND" >DECLARE</TT > declares a cursor for iterating over the result set of a prepared statement. This command has slightly different semantics from the direct SQL command <TT CLASS="COMMAND" >DECLARE</TT >: Whereas the latter executes a query and prepares the result set for retrieval, this embedded SQL command merely declares a name as a <SPAN CLASS="QUOTE" >"loop variable"</SPAN > for iterating over the result set of a query; the actual execution happens when the cursor is opened with the <TT CLASS="COMMAND" >OPEN</TT > command. </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN45316" ></A ><H2 >Parameters</H2 ><P ></P ><DIV CLASS="VARIABLELIST" ><DL ><DT ><TT CLASS="REPLACEABLE" ><I >cursor_name</I ></TT ></DT ><DD ><P > A cursor name, case sensitive. This can be an SQL identifier or a host variable. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >prepared_name</I ></TT ></DT ><DD ><P > The name of a prepared query, either as an SQL identifier or a host variable. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >query</I ></TT ></DT ><DD ><P > A <A HREF="sql-select.html" >SELECT</A > or <A HREF="sql-values.html" >VALUES</A > command which will provide the rows to be returned by the cursor. </P ></DD ></DL ></DIV ><P > For the meaning of the cursor options, see <A HREF="sql-declare.html" >DECLARE</A >. </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN45338" ></A ><H2 >Examples</H2 ><P > Examples declaring a cursor for a query: </P><PRE CLASS="PROGRAMLISTING" >EXEC SQL DECLARE C CURSOR FOR SELECT * FROM My_Table; EXEC SQL DECLARE C CURSOR FOR SELECT Item1 FROM T; EXEC SQL DECLARE cur1 CURSOR FOR SELECT version();</PRE ><P> </P ><P > An example declaring a cursor for a prepared statement: </P><PRE CLASS="PROGRAMLISTING" >EXEC SQL PREPARE stmt1 AS SELECT version(); EXEC SQL DECLARE cur1 CURSOR FOR stmt1;</PRE ><P> </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN45344" ></A ><H2 >Compatibility</H2 ><P > <TT CLASS="COMMAND" >DECLARE</TT > is specified in the SQL standard. </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN45348" ></A ><H2 >See Also</H2 ><A HREF="ecpg-sql-open.html" >OPEN</A >, <A HREF="sql-close.html" >CLOSE</A >, <A HREF="sql-declare.html" >DECLARE</A ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="ecpg-sql-deallocate-descriptor.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="ecpg-sql-describe.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >DEALLOCATE DESCRIPTOR</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="ecpg-sql-commands.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >DESCRIBE</TD ></TR ></TABLE ></DIV ></BODY ></HTML >