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diff --git a/doc/src/sgml/html/contrib-dblink-fetch.html b/doc/src/sgml/html/contrib-dblink-fetch.html new file mode 100644 index 0000000..68d2c12 --- /dev/null +++ b/doc/src/sgml/html/contrib-dblink-fetch.html @@ -0,0 +1,77 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>dblink_fetch</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="contrib-dblink-open.html" title="dblink_open" /><link rel="next" href="contrib-dblink-close.html" title="dblink_close" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">dblink_fetch</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="contrib-dblink-open.html" title="dblink_open">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="dblink.html" title="F.12. dblink">Up</a></td><th width="60%" align="center">F.12. dblink</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="contrib-dblink-close.html" title="dblink_close">Next</a></td></tr></table><hr /></div><div class="refentry" id="CONTRIB-DBLINK-FETCH"><div class="titlepage"></div><a id="id-1.11.7.21.11.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">dblink_fetch</span></h2><p>dblink_fetch — returns rows from an open cursor in a remote database</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis"> +dblink_fetch(text cursorname, int howmany [, bool fail_on_error]) returns setof record +dblink_fetch(text connname, text cursorname, int howmany [, bool fail_on_error]) returns setof record +</pre></div><div class="refsect1" id="id-1.11.7.21.11.5"><h2>Description</h2><p> + <code class="function">dblink_fetch</code> fetches rows from a cursor previously + established by <code class="function">dblink_open</code>. + </p></div><div class="refsect1" id="id-1.11.7.21.11.6"><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>connname</code></em></span></dt><dd><p> + Name of the connection to use; omit this parameter to use the + unnamed connection. + </p></dd><dt><span class="term"><em class="parameter"><code>cursorname</code></em></span></dt><dd><p> + The name of the cursor to fetch from. + </p></dd><dt><span class="term"><em class="parameter"><code>howmany</code></em></span></dt><dd><p> + The maximum number of rows to retrieve. The next <em class="parameter"><code>howmany</code></em> + rows are fetched, starting at the current cursor position, moving + forward. Once the cursor has reached its end, no more rows are produced. + </p></dd><dt><span class="term"><em class="parameter"><code>fail_on_error</code></em></span></dt><dd><p> + If true (the default when omitted) then an error thrown on the + remote side of the connection causes an error to also be thrown + locally. If false, the remote error is locally reported as a NOTICE, + and the function returns no rows. + </p></dd></dl></div></div><div class="refsect1" id="id-1.11.7.21.11.7"><h2>Return Value</h2><p> + The function returns the row(s) fetched from the cursor. To use this + function, you will need to specify the expected set of columns, + as previously discussed for <code class="function">dblink</code>. + </p></div><div class="refsect1" id="id-1.11.7.21.11.8"><h2>Notes</h2><p> + On a mismatch between the number of return columns specified in the + <code class="literal">FROM</code> clause, and the actual number of columns returned by the + remote cursor, an error will be thrown. In this event, the remote cursor + is still advanced by as many rows as it would have been if the error had + not occurred. The same is true for any other error occurring in the local + query after the remote <code class="command">FETCH</code> has been done. + </p></div><div class="refsect1" id="id-1.11.7.21.11.9"><h2>Examples</h2><pre class="screen"> +SELECT dblink_connect('dbname=postgres options=-csearch_path='); + dblink_connect +---------------- + OK +(1 row) + +SELECT dblink_open('foo', 'select proname, prosrc from pg_proc where proname like ''bytea%'''); + dblink_open +------------- + OK +(1 row) + +SELECT * FROM dblink_fetch('foo', 5) AS (funcname name, source text); + funcname | source +----------+---------- + byteacat | byteacat + byteacmp | byteacmp + byteaeq | byteaeq + byteage | byteage + byteagt | byteagt +(5 rows) + +SELECT * FROM dblink_fetch('foo', 5) AS (funcname name, source text); + funcname | source +-----------+----------- + byteain | byteain + byteale | byteale + bytealike | bytealike + bytealt | bytealt + byteane | byteane +(5 rows) + +SELECT * FROM dblink_fetch('foo', 5) AS (funcname name, source text); + funcname | source +------------+------------ + byteanlike | byteanlike + byteaout | byteaout +(2 rows) + +SELECT * FROM dblink_fetch('foo', 5) AS (funcname name, source text); + funcname | source +----------+-------- +(0 rows) +</pre></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="contrib-dblink-open.html" title="dblink_open">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="dblink.html" title="F.12. dblink">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="contrib-dblink-close.html" title="dblink_close">Next</a></td></tr><tr><td width="40%" align="left" valign="top">dblink_open </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="40%" align="right" valign="top"> dblink_close</td></tr></table></div></body></html>
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