📄 function.maxdb-field-count.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>Returns the number of columns for the most recent 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.maxdb-fetch.html">maxdb_fetch</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.maxdb-field-seek.html">maxdb_field_seek</a></div> <div class="up"><a href="ref.maxdb.html">MaxDB Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.maxdb-field-count" class="refentry"> <div class="refnamediv"> <h1 class="refname">maxdb_field_count</h1> <h1 class="refname">maxdb->field_count</h1> <p class="verinfo">(PECL maxdb:1.0-7.6.00.38)</p><p class="refpurpose"><span class="refname">maxdb_field_count</span> -- <span class="refname">maxdb->field_count</span> — <span class="dc-title">Returns the number of columns for the most recent query</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <p class="para">Procedural style:</p> <div class="methodsynopsis dc-description"> <span class="type">int</span> <span class="methodname"><b><b>maxdb_field_count</b></b></span> ( <span class="methodparam"><span class="type">resource</span> <tt class="parameter">$link</tt></span> )</div> <p class="para rdfs-comment">Object oriented style (method):</p> <div class="classsynopsis"> <div class="ooclass"><b class="classname">maxdb</b></div> <div class="methodsynopsis dc-description"> <span class="type">int</span> <span class="methodname"><b><b>field_count</b></b></span> ( <span class="methodparam">void</span> )</div> </div> <p class="para"> Returns the number of columns for the most recent query on the connection represented by the <i><tt class="parameter">link</tt></i> parameter. This function can be useful when using the <a href="function.maxdb-store-result.html" class="function">maxdb_store_result()</a> function to determine if the query should have produced a non-empty result set or not without knowing the nature of the query. </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> An integer representing the number of fields in a result set. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 Object oriented style</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$maxdb </span><span style="color: #007700">= new </span><span style="color: #0000BB">maxdb</span><span style="color: #007700">(</span><span style="color: #DD0000">"localhost"</span><span style="color: #007700">, </span><span style="color: #DD0000">"MONA"</span><span style="color: #007700">, </span><span style="color: #DD0000">"RED"</span><span style="color: #007700">, </span><span style="color: #DD0000">"DEMODB"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">maxdb_report </span><span style="color: #007700">(</span><span style="color: #0000BB">MAXDB_REPORT_OFF</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$maxdb</span><span style="color: #007700">-></span><span style="color: #0000BB">query</span><span style="color: #007700">(</span><span style="color: #DD0000">"DROP TABLE friends"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">maxdb_report </span><span style="color: #007700">(</span><span style="color: #0000BB">MAXDB_REPORT_ERROR</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$maxdb</span><span style="color: #007700">-></span><span style="color: #0000BB">query</span><span style="color: #007700">( </span><span style="color: #DD0000">"CREATE TABLE friends (id int, name varchar(20))"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$maxdb</span><span style="color: #007700">-></span><span style="color: #0000BB">query</span><span style="color: #007700">( </span><span style="color: #DD0000">"INSERT INTO friends VALUES (1,'Hartmut')"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$maxdb</span><span style="color: #007700">-></span><span style="color: #0000BB">query</span><span style="color: #007700">( </span><span style="color: #DD0000">"INSERT INTO friends VALUES (2, 'Ulf')"</span><span style="color: #007700">);<br /><br />if (</span><span style="color: #0000BB">$maxdb</span><span style="color: #007700">-></span><span style="color: #0000BB">field_count</span><span style="color: #007700">()) {<br /> </span><span style="color: #FF8000">/* this was a select/show or describe query */<br /> </span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">$maxdb</span><span style="color: #007700">-></span><span style="color: #0000BB">store_result</span><span style="color: #007700">();<br /><br /> </span><span style="color: #FF8000">/* process resultset */<br /> </span><span style="color: #0000BB">$row </span><span style="color: #007700">= </span><span style="color: #0000BB">$result</span><span style="color: #007700">-></span><span style="color: #0000BB">fetch_row</span><span style="color: #007700">();<br /><br /> </span><span style="color: #FF8000">/* free resultset */<br /> </span><span style="color: #0000BB">$result</span><span style="color: #007700">-></span><span style="color: #0000BB">close</span><span style="color: #007700">();<br />}<br /><br /></span><span style="color: #FF8000">/* close connection */<br /></span><span style="color: #0000BB">$maxdb</span><span style="color: #007700">-></span><span style="color: #0000BB">close</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> <div class="example"> <p><b>Example #2 Procedural style</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$link </span><span style="color: #007700">= </span><span style="color: #0000BB">maxdb_connect</span><span style="color: #007700">(</span><span style="color: #DD0000">"localhost"</span><span style="color: #007700">, </span><span style="color: #DD0000">"MONA"</span><span style="color: #007700">, </span><span style="color: #DD0000">"RED"</span><span style="color: #007700">, </span><span style="color: #DD0000">"DEMODB"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">maxdb_report </span><span style="color: #007700">(</span><span style="color: #0000BB">MAXDB_REPORT_OFF</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">maxdb_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">,</span><span style="color: #DD0000">"DROP TABLE friends"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">maxdb_report </span><span style="color: #007700">(</span><span style="color: #0000BB">MAXDB_REPORT_ERROR</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">maxdb_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">, </span><span style="color: #DD0000">"CREATE TABLE friends (id int, name varchar(20))"</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">maxdb_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">, </span><span style="color: #DD0000">"INSERT INTO friends VALUES (1,'Hartmut')"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">maxdb_query</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">, </span><span style="color: #DD0000">"INSERT INTO friends VALUES (2, 'Ulf')"</span><span style="color: #007700">);<br /><br />if (</span><span style="color: #0000BB">maxdb_field_count</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">)) {<br /> </span><span style="color: #FF8000">/* this was a select/show or describe query */<br /> </span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">maxdb_store_result</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">);<br /><br /> </span><span style="color: #FF8000">/* process resultset */<br /> </span><span style="color: #0000BB">$row </span><span style="color: #007700">= </span><span style="color: #0000BB">maxdb_fetch_row</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">);<br /><br /> </span><span style="color: #FF8000">/* free resultset */<br /> </span><span style="color: #0000BB">maxdb_free_result</span><span style="color: #007700">(</span><span style="color: #0000BB">$result</span><span style="color: #007700">);<br />}<br /><br /></span><span style="color: #FF8000">/* close connection */<br /></span><span style="color: #0000BB">maxdb_close</span><span style="color: #007700">(</span><span style="color: #0000BB">$link</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> <p class="para"> The above example produces no output. </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.maxdb-fetch.html">maxdb_fetch</a></div> <div class="next" style="text-align: right; 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