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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 >pg_cursors</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="System Catalogs" HREF="catalogs.html"><LINK REL="PREVIOUS" TITLE="pg_available_extension_versions" HREF="view-pg-available-extension-versions.html"><LINK REL="NEXT" TITLE="pg_group" HREF="view-pg-group.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="SECT1" ><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="pg_available_extension_versions" HREF="view-pg-available-extension-versions.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="catalogs.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" >Chapter 45. System Catalogs</TD ><TD WIDTH="20%" ALIGN="right" VALIGN="top" ><A TITLE="pg_group" HREF="view-pg-group.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="VIEW-PG-CURSORS" >45.55. <TT CLASS="STRUCTNAME" >pg_cursors</TT ></A ></H1 ><P > The <TT CLASS="STRUCTNAME" >pg_cursors</TT > view lists the cursors that are currently available. Cursors can be defined in several ways: <P ></P ></P><UL ><LI ><P > via the <A HREF="sql-declare.html" >DECLARE</A > statement in SQL </P ></LI ><LI ><P > via the Bind message in the frontend/backend protocol, as described in <A HREF="protocol-flow.html#PROTOCOL-FLOW-EXT-QUERY" >Section 46.2.3</A > </P ></LI ><LI ><P > via the Server Programming Interface (SPI), as described in <A HREF="spi-interface.html" >Section 43.1</A > </P ></LI ></UL ><P> The <TT CLASS="STRUCTNAME" >pg_cursors</TT > view displays cursors created by any of these means. Cursors only exist for the duration of the transaction that defines them, unless they have been declared <TT CLASS="LITERAL" >WITH HOLD</TT >. Therefore non-holdable cursors are only present in the view until the end of their creating transaction. </P><DIV CLASS="NOTE" ><BLOCKQUOTE CLASS="NOTE" ><P ><B >Note: </B > Cursors are used internally to implement some of the components of <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN >, such as procedural languages. Therefore, the <TT CLASS="STRUCTNAME" >pg_cursors</TT > view might include cursors that have not been explicitly created by the user. </P ></BLOCKQUOTE ></DIV ><P> </P ><DIV CLASS="TABLE" ><A NAME="AEN94145" ></A ><P ><B >Table 45-56. <TT CLASS="STRUCTNAME" >pg_cursors</TT > Columns</B ></P ><TABLE BORDER="1" CLASS="CALSTABLE" ><COL><COL><COL><THEAD ><TR ><TH >Name</TH ><TH >Type</TH ><TH >Description</TH ></TR ></THEAD ><TBODY ><TR ><TD ><TT CLASS="STRUCTFIELD" >name</TT ></TD ><TD ><TT CLASS="TYPE" >text</TT ></TD ><TD >The name of the cursor</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >statement</TT ></TD ><TD ><TT CLASS="TYPE" >text</TT ></TD ><TD >The verbatim query string submitted to declare this cursor</TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >is_holdable</TT ></TD ><TD ><TT CLASS="TYPE" >boolean</TT ></TD ><TD > <TT CLASS="LITERAL" >true</TT > if the cursor is holdable (that is, it can be accessed after the transaction that declared the cursor has committed); <TT CLASS="LITERAL" >false</TT > otherwise </TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >is_binary</TT ></TD ><TD ><TT CLASS="TYPE" >boolean</TT ></TD ><TD > <TT CLASS="LITERAL" >true</TT > if the cursor was declared <TT CLASS="LITERAL" >BINARY</TT >; <TT CLASS="LITERAL" >false</TT > otherwise </TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >is_scrollable</TT ></TD ><TD ><TT CLASS="TYPE" >boolean</TT ></TD ><TD > <TT CLASS="LITERAL" >true</TT > if the cursor is scrollable (that is, it allows rows to be retrieved in a nonsequential manner); <TT CLASS="LITERAL" >false</TT > otherwise </TD ></TR ><TR ><TD ><TT CLASS="STRUCTFIELD" >creation_time</TT ></TD ><TD ><TT CLASS="TYPE" >timestamptz</TT ></TD ><TD >The time at which the cursor was declared</TD ></TR ></TBODY ></TABLE ></DIV ><P > The <TT CLASS="STRUCTNAME" >pg_cursors</TT > view is read only. </P ></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="view-pg-available-extension-versions.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="view-pg-group.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><TT CLASS="STRUCTNAME" >pg_available_extension_versions</TT ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="catalogs.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><TT CLASS="STRUCTNAME" >pg_group</TT ></TD ></TR ></TABLE ></DIV ></BODY ></HTML >