📄 function.mysql-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>Send a MySQL 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.mysql-ping.html">mysql_ping</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.mysql-real-escape-string.html">mysql_real_escape_string</a></div> <div class="up"><a href="ref.mysql.html">MySQL Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.mysql-query" class="refentry"> <div class="refnamediv"> <h1 class="refname">mysql_query</h1> <p class="verinfo">(PHP 4, PHP 5, PECL mysql:1.0)</p><p class="refpurpose"><span class="refname">mysql_query</span> — <span class="dc-title">Send a MySQL 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>mysql_query</b></b></span> ( <span class="methodparam"><span class="type">string</span> <tt class="parameter">$query</tt></span> [, <span class="methodparam"><span class="type">resource</span> <tt class="parameter">$link_identifier</tt></span> ] )</div> <p class="para rdfs-comment"> <b>mysql_query()</b> sends an unique query (multiple queries are not supported) to the currently active database on the server that's associated with the specified <i><tt class="parameter">link_identifier</tt></i>. </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">query</tt></i></span> <dd> <p class="para"> A SQL query </p> <p class="para"> The query string should not end with a semicolon. </p> </dd> </dt> <dt><span class="term"><i><tt class="parameter">link_identifier</tt></i></span><dd><p class="para">The MySQL connection. If the link identifier is not specified, the last link opened by <a href="function.mysql-connect.html" class="function">mysql_connect()</a> is assumed. If no such link is found, itwill try to create one as if <a href="function.mysql-connect.html" class="function">mysql_connect()</a> was calledwith no arguments. If by chance no connection is found or established, an<b><tt>E_WARNING</tt></b> level error is generated.</p></dd></dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> For SELECT, SHOW, DESCRIBE, EXPLAIN and other statements returning resultset, <b>mysql_query()</b> returns a <a href="language.types.resource.html" class="type resource">resource</a> on success, or <b><tt>FALSE</tt></b> on error. </p> <p class="para"> For other type of SQL statements, INSERT, UPDATE, DELETE, DROP, etc, <b>mysql_query()</b> returns <b><tt>TRUE</tt></b> on success or <b><tt>FALSE</tt></b> on error. </p> <p class="para"> The returned result resource should be passed to <a href="function.mysql-fetch-array.html" class="function">mysql_fetch_array()</a>, and other functions for dealing with result tables, to access the returned data. </p> <p class="para"> Use <a href="function.mysql-num-rows.html" class="function">mysql_num_rows()</a> to find out how many rows were returned for a SELECT statement or <a href="function.mysql-affected-rows.html" class="function">mysql_affected_rows()</a> to find out how many rows were affected by a DELETE, INSERT, REPLACE, or UPDATE statement. </p> <p class="para"> <b>mysql_query()</b> will also fail and return <b><tt>FALSE</tt></b> if the user does not have permission to access the table(s) referenced by the query. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 Invalid Query</b></p> <div class="example-contents"><p> The following query is syntactically invalid, so <b>mysql_query()</b> fails and returns <b><tt>FALSE</tt></b>. </p></div> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$result </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_query</span><span style="color: #007700">(</span><span style="color: #DD0000">'SELECT * WHERE 1=1'</span><span style="color: #007700">);<br />if (!</span><span style="color: #0000BB">$result</span><span style="color: #007700">) {<br /> die(</span><span style="color: #DD0000">'Invalid query: ' </span><span style="color: #007700">. </span><span style="color: #0000BB">mysql_error</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 Valid Query</b></p> <div class="example-contents"><p> The following query is valid, so <b>mysql_query()</b> returns a <a href="language.types.resource.html" class="type resource">resource</a>. </p></div> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// This could be supplied by a user, for example<br /></span><span style="color: #0000BB">$firstname </span><span style="color: #007700">= </span><span style="color: #DD0000">'fred'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$lastname </span><span style="color: #007700">= </span><span style="color: #DD0000">'fox'</span><span style="color: #007700">;<br /><br /></span><span style="color: #FF8000">// Formulate Query<br />// This is the best way to perform a SQL query<br />// For more examples, see mysql_real_escape_string()<br /></span><span style="color: #0000BB">$query </span><span style="color: #007700">= </span><span style="color: #0000BB">sprintf</span><span style="color: #007700">(</span><span style="color: #DD0000">"SELECT firstname, lastname, address, age FROM friends WHERE firstname='%s' AND lastname='%s'"</span><span style="color: #007700">,<br /> </span><span style="color: #0000BB">mysql_real_escape_string</span><span style="color: #007700">(</span><span style="color: #0000BB">$firstname</span><span style="color: #007700">),<br /> </span><span style="color: #0000BB">mysql_real_escape_string</span><span style="color: #007700">(</span><span style="color: #0000BB">$lastname</span><span style="color: #007700">));<br /><br /></span><span style="color: #FF8000">// Perform Query<br /></span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$query</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Check result<br />// This shows the actual query sent to MySQL, and the error. Useful for debugging.<br /></span><span style="color: #007700">if (!</span><span style="color: #0000BB">$result</span><span style="color: #007700">) {<br /> </span><span style="color: #0000BB">$message </span><span style="color: #007700">= </span><span style="color: #DD0000">'Invalid query: ' </span><span style="color: #007700">. </span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">() . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /> </span><span style="color: #0000BB">$message </span><span style="color: #007700">.= </span><span style="color: #DD0000">'Whole query: ' </span><span style="color: #007700">. </span><span style="color: #0000BB">$query</span><span style="color: #007700">;<br /> die(</span><span style="color: #0000BB">$message</span><span style="color: #007700">);<br />}<br /><br /></span><span style="color: #FF8000">// Use result<br />// Attempting to print $result won't allow access to information in the resource<br />// One of the mysql result functions must be used<br />// See also mysql_result(), mysql_fetch_array(), mysql_fetch_row(), etc.<br /></span><span style="color: #007700">while (</span><span style="color: #0000BB">$row </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_fetch_assoc</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">)) {<br /> echo </span><span style="color: #0000BB">$row</span><span style="color: #007700">[</span><span style="color: #DD0000">'firstname'</span><span style="color: #007700">];<br /> echo </span><span style="color: #0000BB">$row</span><span style="color: #007700">[</span><span style="color: #DD0000">'lastname'</span><span style="color: #007700">];<br /> echo </span><span style="color: #0000BB">$row</span><span style="color: #007700">[</span><span style="color: #DD0000">'address'</span><span style="color: #007700">];<br /> echo </span><span style="color: #0000BB">$row</span><span style="color: #007700">[</span><span style="color: #DD0000">'age'</span><span style="color: #007700">];<br />}<br /><br /></span><span style="color: #FF8000">// Free the resources associated with the result set<br />// This is done automatically at the end of the script<br /></span><span style="color: #0000BB">mysql_free_result</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">);<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.mysql-connect.html" class="function" rel="rdfs-seeAlso">mysql_connect()</a></li> <li class="member"><a href="function.mysql-error.html" class="function" rel="rdfs-seeAlso">mysql_error()</a></li> <li class="member"><a href="function.mysql-real-escape-string.html" class="function" rel="rdfs-seeAlso">mysql_real_escape_string()</a></li> <li class="member"><a href="function.mysql-result.html" class="function" rel="rdfs-seeAlso">mysql_result()</a></li> <li class="member"><a href="function.mysql-fetch-assoc.html" class="function" rel="rdfs-seeAlso">mysql_fetch_assoc()</a></li> <li class="member"><a href="function.mysql-unbuffered-query.html" class="function" rel="rdfs-seeAlso">mysql_unbuffered_query()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.mysql-ping.html">mysql_ping</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.mysql-real-escape-string.html">mysql_real_escape_string</a></div> <div class="up"><a href="ref.mysql.html">MySQL Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div></body></html>⌨️ 快捷键说明
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