function.pg-query.html
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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>Execute a query</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.pg-query-params.html">pg_query_params</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.pg-result-error-field.html">pg_result_error_field</a></div> <div class="up"><a href="ref.pgsql.html">PostgreSQL Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.pg-query" class="refentry"> <div class="refnamediv"> <h1 class="refname">pg_query</h1> <p class="verinfo">(PHP 4 >= 4.2.0, PHP 5)</p><p class="refpurpose"><span class="refname">pg_query</span> — <span class="dc-title">Execute a query</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">resource</span> <span class="methodname"><b><b>pg_query</b></b></span> ( <span class="methodparam"><span class="type">string</span> <tt class="parameter">$query</tt></span> )</div> <div class="methodsynopsis dc-description"> <span class="type">resource</span> <span class="methodname"><b><b>pg_query</b></b></span> ( <span class="methodparam"><span class="type">resource</span> <tt class="parameter">$connection</tt></span> , <span class="methodparam"><span class="type">string</span> <tt class="parameter">$query</tt></span> )</div> <p class="para rdfs-comment"> <b>pg_query()</b> executes the <i><tt class="parameter">query</tt></i> on the specified database <i><tt class="parameter">connection</tt></i>. </p> <p class="para"> If an error occurs, and <b><tt>FALSE</tt></b> is returned, details of the error can be retrieved using the <a href="function.pg-last-error.html" class="function">pg_last_error()</a> function if the connection is valid. </p> <p class="para"> <blockquote><p><b class="note">Note</b>: <span class="simpara"> Although <i><tt class="parameter">connection</tt></i> can be omitted, it is not recommended, since it can be the cause of hard to find bugs in scripts. </span> </p></blockquote> </p> <blockquote><p><b class="note">Note</b>: This function used to be called <b>pg_exec()</b>. <b>pg_exec()</b> is still available for compatibility reasons, but users are encouraged to use the newer name. <br /> </p></blockquote> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">connection</tt></i></span> <dd> <p class="para"> PostgreSQL database connection resource. When <i><tt class="parameter">connection</tt></i> is not present, the default connection is used. The default connection is the last connection made by <a href="function.pg-connect.html" class="function">pg_connect()</a> or <a href="function.pg-pconnect.html" class="function">pg_pconnect()</a>. </p> </dd> </dt> <dt> <span class="term"><i><tt class="parameter">query</tt></i></span> <dd> <p class="para"> The SQL statement or statements to be executed. When multiple statements are passed to the function, they are automatically executed as one transaction, unless there are explicit BEGIN/COMMIT commands included in the query string. However, using multiple transactions in one function call is not recommended. </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> A query result resource on success, or <b><tt>FALSE</tt></b> on failure. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 <b>pg_query()</b> example</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br /><br />$conn </span><span style="color: #007700">= </span><span style="color: #0000BB">pg_pconnect</span><span style="color: #007700">(</span><span style="color: #DD0000">"dbname=publisher"</span><span style="color: #007700">);<br />if (!</span><span style="color: #0000BB">$conn</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"An error occured.\n"</span><span style="color: #007700">;<br /> exit;<br />}<br /><br /></span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">pg_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$conn</span><span style="color: #007700">, </span><span style="color: #DD0000">"SELECT author, email FROM authors"</span><span style="color: #007700">);<br />if (!</span><span style="color: #0000BB">$result</span><span style="color: #007700">) {<br /> echo </span><span style="color: #DD0000">"An error occured.\n"</span><span style="color: #007700">;<br /> exit;<br />}<br /><br />while (</span><span style="color: #0000BB">$row </span><span style="color: #007700">= </span><span style="color: #0000BB">pg_fetch_row</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">)) {<br /> echo </span><span style="color: #DD0000">"Author: $row[0] E-mail: $row[1]"</span><span style="color: #007700">;<br /> echo </span><span style="color: #DD0000">"<br />\n"</span><span style="color: #007700">;<br />}<br /> <br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> <p class="para"> <div class="example"> <p><b>Example #2 Using <b>pg_query()</b> with multiple statements</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br /><br />$conn </span><span style="color: #007700">= </span><span style="color: #0000BB">pg_pconnect</span><span style="color: #007700">(</span><span style="color: #DD0000">"dbname=publisher"</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// these statements will be executed as one transaction<br /><br /></span><span style="color: #0000BB">$query </span><span style="color: #007700">= </span><span style="color: #DD0000">"UPDATE authors SET author=UPPER(author) WHERE id=1;"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$query </span><span style="color: #007700">.= </span><span style="color: #DD0000">"UPDATE authors SET author=LOWER(author) WHERE id=2;"</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$query </span><span style="color: #007700">.= </span><span style="color: #DD0000">"UPDATE authors SET author=NULL WHERE id=3;"</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">pg_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$conn</span><span style="color: #007700">, </span><span style="color: #0000BB">$query</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.pg-connect.html" class="function" rel="rdfs-seeAlso">pg_connect()</a></li> <li class="member"><a href="function.pg-pconnect.html" class="function" rel="rdfs-seeAlso">pg_pconnect()</a></li> <li class="member"><a href="function.pg-fetch-array.html" class="function" rel="rdfs-seeAlso">pg_fetch_array()</a></li> <li class="member"><a href="function.pg-fetch-object.html" class="function" rel="rdfs-seeAlso">pg_fetch_object()</a></li> <li class="member"><a href="function.pg-num-rows.html" class="function" rel="rdfs-seeAlso">pg_num_rows()</a></li> <li class="member"><a href="function.pg-affected-rows.html" class="function" rel="rdfs-seeAlso">pg_affected_rows()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; 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