<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >maxdb_field_count</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REL="HOME" TITLE="PHP 手册" HREF="index.html"><LINK REL="UP" TITLE="MaxDB PHP Extension" HREF="ref.maxdb.html"><LINK REL="PREVIOUS" TITLE="maxdb_fetch" HREF="function.maxdb-fetch.html"><LINK REL="NEXT" TITLE="maxdb_field_seek" HREF="function.maxdb-field-seek.html"><META HTTP-EQUIV="Content-type" CONTENT="text/html; charset=UTF-8"></HEAD ><BODY CLASS="refentry" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >PHP 手册</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="function.maxdb-fetch.html" ACCESSKEY="P" >上一页</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="function.maxdb-field-seek.html" ACCESSKEY="N" >下一页</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="function.maxdb-field-count" ></A >maxdb_field_count</H1 ><DIV CLASS="refnamediv" ><A NAME="AEN110983" ></A ><P > (PECL)</P >maxdb_field_count<P > (no version information, might be only in CVS)</P >maxdb->field_count -- Returns the number of columns for the most recent query</DIV ><DIV CLASS="refsect1" ><A NAME="AEN110987" ></A ><H2 >Description</H2 ><P >Procedural style:</P >int <B CLASS="methodname" >maxdb_field_count</B > ( resource link )<BR ></BR ><P >Object oriented style (method):</P >class <B CLASS="classname" >maxdb</B > { <BR ></BR >int <B CLASS="methodname" >field_count</B > ( void )<BR ></BR >}<P > Returns the number of columns for the most recent query on the connection represented by the <CODE CLASS="parameter" >link</CODE > parameter. This function can be useful when using the <A HREF="function.maxdb-store-result.html" ><B CLASS="function" >maxdb_store_result()</B ></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" ><A NAME="AEN111007" ></A ><H2 >Return values</H2 ><P >An integer representing the number of fields in a result set</P ></DIV ><DIV CLASS="refsect1" ><A NAME="AEN111010" ></A ><H2 >Example</H2 ><P > <TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" CLASS="EXAMPLE" ><TR ><TD ><DIV CLASS="example" ><A NAME="AEN111013" ></A ><P ><B >例 1. Object oriented style</B ></P ><TABLE BORDER="0" BGCOLOR="#E0E0E0" CELLPADDING="5" ><TR ><TD ><code><font color="#000000"> <font color="#0000BB"><?php<br />$maxdb </font><font color="#007700">= new </font><font color="#0000BB">maxdb</font><font color="#007700">(</font><font color="#DD0000">"localhost"</font><font color="#007700">, </font><font color="#DD0000">"MONA"</font><font color="#007700">, </font><font color="#DD0000">"RED"</font><font color="#007700">, </font><font color="#DD0000">"DEMODB"</font><font color="#007700">);<br /><br /></font><font color="#0000BB">maxdb_report </font><font color="#007700">(</font><font color="#0000BB">MAXDB_REPORT_OFF</font><font color="#007700">);<br /></font><font color="#0000BB">$maxdb</font><font color="#007700">-></font><font color="#0000BB">query</font><font color="#007700">(</font><font color="#DD0000">"DROP TABLE friends"</font><font color="#007700">);<br /></font><font color="#0000BB">maxdb_report </font><font color="#007700">(</font><font color="#0000BB">MAXDB_REPORT_ERROR</font><font color="#007700">);<br /><br /></font><font color="#0000BB">$maxdb</font><font color="#007700">-></font><font color="#0000BB">query</font><font color="#007700">( </font><font color="#DD0000">"CREATE TABLE friends (id int, name varchar(20))"</font><font color="#007700">);<br /><br /></font><font color="#0000BB">$maxdb</font><font color="#007700">-></font><font color="#0000BB">query</font><font color="#007700">( </font><font color="#DD0000">"INSERT INTO friends VALUES (1,'Hartmut')"</font><font color="#007700">);<br /></font><font color="#0000BB">$maxdb</font><font color="#007700">-></font><font color="#0000BB">query</font><font color="#007700">( </font><font color="#DD0000">"INSERT INTO friends VALUES (2, 'Ulf')"</font><font color="#007700">);<br /><br />if (</font><font color="#0000BB">$maxdb</font><font color="#007700">-></font><font color="#0000BB">field_count</font><font color="#007700">()) {<br /> </font><font color="#FF8000">/* this was a select/show or describe query */<br /> </font><font color="#0000BB">$result </font><font color="#007700">= </font><font color="#0000BB">$maxdb</font><font color="#007700">-></font><font color="#0000BB">store_result</font><font color="#007700">();<br /><br /> </font><font color="#FF8000">/* process resultset */<br /> </font><font color="#0000BB">$row </font><font color="#007700">= </font><font color="#0000BB">$result</font><font color="#007700">-></font><font color="#0000BB">fetch_row</font><font color="#007700">();<br /><br /> </font><font color="#FF8000">/* free resultset */<br /> </font><font color="#0000BB">$result</font><font color="#007700">-></font><font color="#0000BB">close</font><font color="#007700">();<br />}<br /><br /></font><font color="#FF8000">/* close connection */<br /></font><font color="#0000BB">$maxdb</font><font color="#007700">-></font><font color="#0000BB">close</font><font color="#007700">();<br /></font><font color="#0000BB">?></font> </font> </code></TD ></TR ></TABLE ></DIV ></TD ></TR ></TABLE > <TABLE WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" CLASS="EXAMPLE" ><TR ><TD ><DIV CLASS="example" ><A NAME="AEN111016" ></A ><P ><B >例 2. Procedural style</B ></P ><TABLE BORDER="0" BGCOLOR="#E0E0E0" CELLPADDING="5" ><TR ><TD ><code><font color="#000000"> <font color="#0000BB"><?php<br />$link </font><font color="#007700">= </font><font color="#0000BB">maxdb_connect</font><font color="#007700">(</font><font color="#DD0000">"localhost"</font><font color="#007700">, </font><font color="#DD0000">"MONA"</font><font color="#007700">, </font><font color="#DD0000">"RED"</font><font color="#007700">, </font><font color="#DD0000">"DEMODB"</font><font color="#007700">);<br /><br /></font><font color="#0000BB">maxdb_report </font><font color="#007700">(</font><font color="#0000BB">MAXDB_REPORT_OFF</font><font color="#007700">);<br /></font><font color="#0000BB">maxdb_query</font><font color="#007700">(</font><font color="#0000BB">$link</font><font color="#007700">,</font><font color="#DD0000">"DROP TABLE friends"</font><font color="#007700">);<br /></font><font color="#0000BB">maxdb_report </font><font color="#007700">(</font><font color="#0000BB">MAXDB_REPORT_ERROR</font><font color="#007700">);<br /><br /></font><font color="#0000BB">maxdb_query</font><font color="#007700">(</font><font color="#0000BB">$link</font><font color="#007700">, </font><font color="#DD0000">"CREATE TABLE friends (id int, name varchar(20))"</font><font color="#007700">);<br /><br /></font><font color="#0000BB">maxdb_query</font><font color="#007700">(</font><font color="#0000BB">$link</font><font color="#007700">, </font><font color="#DD0000">"INSERT INTO friends VALUES (1,'Hartmut')"</font><font color="#007700">);<br /></font><font color="#0000BB">maxdb_query</font><font color="#007700">(</font><font color="#0000BB">$link</font><font color="#007700">, </font><font color="#DD0000">"INSERT INTO friends VALUES (2, 'Ulf')"</font><font color="#007700">);<br /><br />if (</font><font color="#0000BB">maxdb_field_count</font><font color="#007700">(</font><font color="#0000BB">$link</font><font color="#007700">)) {<br /> </font><font color="#FF8000">/* this was a select/show or describe query */<br /> </font><font color="#0000BB">$result </font><font color="#007700">= </font><font color="#0000BB">maxdb_store_result</font><font color="#007700">(</font><font color="#0000BB">$link</font><font color="#007700">);<br /><br /> </font><font color="#FF8000">/* process resultset */<br /> </font><font color="#0000BB">$row </font><font color="#007700">= </font><font color="#0000BB">maxdb_fetch_row</font><font color="#007700">(</font><font color="#0000BB">$result</font><font color="#007700">);<br /><br /> </font><font color="#FF8000">/* free resultset */<br /> </font><font color="#0000BB">maxdb_free_result</font><font color="#007700">(</font><font color="#0000BB">$result</font><font color="#007700">);<br />}<br /><br /></font><font color="#FF8000">/* close connection */<br /></font><font color="#0000BB">maxdb_close</font><font color="#007700">(</font><font color="#0000BB">$link</font><font color="#007700">);<br /></font><font color="#0000BB">?></font> </font> </code></TD ></TR ></TABLE ></DIV ></TD ></TR ></TABLE > </P ><P > The above example produces no output. </P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="function.maxdb-fetch.html" ACCESSKEY="P" >上一页</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >起始页</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="function.maxdb-field-seek.html" ACCESSKEY="N" >下一页</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >maxdb_fetch</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="ref.maxdb.html" ACCESSKEY="U" >上一级</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >maxdb_field_seek</TD ></TR ></TABLE ></DIV ></BODY ></HTML >