📄 function.mysql-data-seek.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>Move internal result pointer</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-create-db.html">mysql_create_db</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.mysql-db-name.html">mysql_db_name</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-data-seek" class="refentry"> <div class="refnamediv"> <h1 class="refname">mysql_data_seek</h1> <p class="verinfo">(PHP 4, PHP 5, PECL mysql:1.0)</p><p class="refpurpose"><span class="refname">mysql_data_seek</span> — <span class="dc-title">Move internal result pointer</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">bool</span> <span class="methodname"><b><b>mysql_data_seek</b></b></span> ( <span class="methodparam"><span class="type">resource</span> <tt class="parameter">$result</tt></span> , <span class="methodparam"><span class="type">int</span> <tt class="parameter">$row_number</tt></span> )</div> <p class="para rdfs-comment"> <b>mysql_data_seek()</b> moves the internal row pointer of the MySQL result associated with the specified result identifier to point to the specified row number. The next call to a MySQL fetch function, such as <a href="function.mysql-fetch-assoc.html" class="function">mysql_fetch_assoc()</a>, would return that row. </p> <p class="para"> <i><tt class="parameter">row_number</tt></i> starts at 0. The <i><tt class="parameter">row_number</tt></i> should be a value in the range from 0 to <a href="function.mysql-num-rows.html" class="function">mysql_num_rows()</a> - 1. However if the result set is empty (<a href="function.mysql-num-rows.html" class="function">mysql_num_rows()</a> == 0), a seek to 0 will fail with a <a href="errorfunc.constants.html#errorfunc.constants.errorlevels.e-warning" class="link">E_WARNING</a> and <b>mysql_data_seek()</b> will return <b><tt>FALSE</tt></b>. </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt><span class="term"><i><tt class="parameter">result</tt></i></span><dd><p class="para">The result <a href="language.types.resource.html" class="type resource">resource</a> thatis being evaluated. This result comes from a call to <a href="function.mysql-query.html" class="function">mysql_query()</a>.</p></dd></dt> <dt> <span class="term"><i><tt class="parameter">row_number</tt></i></span> <dd> <p class="para"> The desired row number of the new result pointer. </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns <b><tt>TRUE</tt></b> 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>mysql_data_seek()</b> example</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$link </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">'localhost'</span><span style="color: #007700">, </span><span style="color: #DD0000">'mysql_user'</span><span style="color: #007700">, </span><span style="color: #DD0000">'mysql_password'</span><span style="color: #007700">);<br />if (!</span><span style="color: #0000BB">$link</span><span style="color: #007700">) {<br /> die(</span><span style="color: #DD0000">'Could not connect: ' </span><span style="color: #007700">. </span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">());<br />}<br /></span><span style="color: #0000BB">$db_selected </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_select_db</span><span style="color: #007700">(</span><span style="color: #DD0000">'sample_db'</span><span style="color: #007700">);<br />if (!</span><span style="color: #0000BB">$db_selected</span><span style="color: #007700">) {<br /> die(</span><span style="color: #DD0000">'Could not select database: ' </span><span style="color: #007700">. </span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">());<br />}<br /></span><span style="color: #0000BB">$query </span><span style="color: #007700">= </span><span style="color: #DD0000">'SELECT last_name, first_name FROM friends'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$query</span><span style="color: #007700">);<br />if (!</span><span style="color: #0000BB">$result</span><span style="color: #007700">) {<br /> die(</span><span style="color: #DD0000">'Query failed: ' </span><span style="color: #007700">. </span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">());<br />}<br /></span><span style="color: #FF8000">/* fetch rows in reverse order */<br /></span><span style="color: #007700">for (</span><span style="color: #0000BB">$i </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_num_rows</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">) - </span><span style="color: #0000BB">1</span><span style="color: #007700">; </span><span style="color: #0000BB">$i </span><span style="color: #007700">>= </span><span style="color: #0000BB">0</span><span style="color: #007700">; </span><span style="color: #0000BB">$i</span><span style="color: #007700">--) {<br /> if (!</span><span style="color: #0000BB">mysql_data_seek</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">, </span><span style="color: #0000BB">$i</span><span style="color: #007700">)) {<br /> echo </span><span style="color: #DD0000">"Cannot seek to row $i: " </span><span style="color: #007700">. </span><span style="color: #0000BB">mysql_error</span><span style="color: #007700">() . </span><span style="color: #DD0000">"\n"</span><span style="color: #007700">;<br /> continue;<br /> }<br /><br /> if (!(</span><span style="color: #0000BB">$row </span><span style="color: #007700">= </span><span style="color: #0000BB">mysql_fetch_assoc</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">))) {<br /> continue;<br /> }<br /><br /> echo </span><span style="color: #0000BB">$row</span><span style="color: #007700">[</span><span style="color: #DD0000">'last_name'</span><span style="color: #007700">] . </span><span style="color: #DD0000">' ' </span><span style="color: #007700">. </span><span style="color: #0000BB">$row</span><span style="color: #007700">[</span><span style="color: #DD0000">'first_name'</span><span style="color: #007700">] . </span><span style="color: #DD0000">"<br />\n"</span><span style="color: #007700">;<br />}<br /><br /></span><span style="color: #0000BB">mysql_free_result</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> </div> <div class="refsect1 notes"> <h3 class="title">Notes</h3> <blockquote><p><b class="note">Note</b>: The function <b>mysql_data_seek()</b> can be used in conjunction only with <a href="function.mysql-query.html" class="function">mysql_query()</a>, not with <a href="function.mysql-unbuffered-query.html" class="function">mysql_unbuffered_query()</a>. <br /> </p></blockquote> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.mysql-query.html" class="function" rel="rdfs-seeAlso">mysql_query()</a></li> <li class="member"><a href="function.mysql-num-rows.html" class="function" rel="rdfs-seeAlso">mysql_num_rows()</a></li> <li class="member"><a href="function.mysql-fetch-row.html" class="function" rel="rdfs-seeAlso">mysql_fetch_row()</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-fetch-array.html" class="function" rel="rdfs-seeAlso">mysql_fetch_array()</a></li> <li class="member"><a href="function.mysql-fetch-object.html" class="function" rel="rdfs-seeAlso">mysql_fetch_object()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; 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