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<refentry xml:id="function.sqlsrv-prepare" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
 <refnamediv>
  <refname>sqlsrv_prepare</refname>
  <refpurpose>Prepares a query for execution</refpurpose>
 </refnamediv>
 <refsect1 role="description">
  &reftitle.description;
  <methodsynopsis>
   <type>mixed</type><methodname>sqlsrv_prepare</methodname>
   <methodparam><type>resource</type><parameter>conn</parameter></methodparam>
   <methodparam><type>string</type><parameter>sql</parameter></methodparam>
   <methodparam choice="opt"><type>array</type><parameter>params</parameter></methodparam>
   <methodparam choice="opt"><type>array</type><parameter>options</parameter></methodparam>
  </methodsynopsis>
  <para>
   Prepares a query for execution. This function is ideal for preparing a query 
   that will be executed multiple times with different parameter values.
  </para>
 </refsect1>
 
 <refsect1 role="parameters">
  &reftitle.parameters;
  <para>
   <variablelist>
    <varlistentry>
     <term><parameter>conn</parameter></term>
     <listitem>
      <para>
       A connection resource returned by <function>sqlsrv_connect</function>.
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>sql</parameter></term>
     <listitem>
      <para>
       The string that defines the query to be prepared and executed.
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>params</parameter></term>
     <listitem>
      <para>
       An array specifying parameter information when executing a parameterized 
       query. Array elements can be any of the following:
       <simplelist>
        <member>A literal value</member>
        <member>A PHP variable</member>
        <member>An array with this structure: 
        array($value [, $direction [, $phpType [, $sqlType]]])</member>
       </simplelist>
       The following table describes the elements in the array structure above:
       </para>
       <table>
       <title>Array structure</title>
       <tgroup cols="2">
        <thead>
         <row>
          <entry>Element</entry>
          <entry>Description</entry>
         </row>
        </thead>
        <tbody>
         <row>
          <entry>$value</entry>
          <entry>A literal value, a PHP variable, or a PHP by-reference variable.</entry>
         </row>
         <row>
          <entry>$direction (optional)</entry>
          <entry>One of the following SQLSRV constants used to indicate the 
          parameter direction: SQLSRV_PARAM_IN, SQLSRV_PARAM_OUT, SQLSRV_PARAM_INOUT. 
          The default value is SQLSRV_PARAM_IN.         </entry>
         </row>
         <row>
          <entry>$phpType (optional)</entry>
          <entry>A SQLSRV_PHPTYPE_* constant that specifies PHP data type of the 
          returned value.</entry>
         </row>
         <row>
          <entry>$sqlType (optional)</entry>
          <entry>A SQLSRV_SQLTYPE_* constant that specifies the SQL Server data 
          type of the input value.</entry>
         </row>
        </tbody>
       </tgroup>
      </table>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>options</parameter></term>
     <listitem>
      <para>
       An array specifying query property options. The supported keys are described 
       in the following table:
      </para>
      <table>
       <title>Query Options</title>
       <tgroup cols="3">
        <thead>
         <row>
          <entry>Key</entry>
          <entry>Values</entry>
          <entry>Description</entry>
         </row>
        </thead>
        <tbody>
         <row>
          <entry>QueryTimeout</entry>
          <entry>A positive integer value.</entry>
          <entry>Sets the query timeout in seconds. By default, the driver will 
          wait indefinitely for results.</entry>
         </row>
         <row>
          <entry>SendStreamParamsAtExec</entry>
          <entry>&true; or &false; (the default is &true;)</entry>
          <entry>Configures the driver to send all stream data at execution (&true;), 
          or to send stream data in chunks (&false;). By default, the value is set to &true;. 
          For more information, see <function>sqlsrv_send_stream_data</function>.</entry>
         </row>
         <row>
          <entry>Scrollable</entry>
          <entry>SQLSRV_CURSOR_FORWARD, SQLSRV_CURSOR_STATIC, SQLSRV_CURSOR_DYNAMIC, 
          or SQLSRV_CURSOR_KEYSET</entry>
          <entry>See <link xlink:href="&url.sqlsrv.specify.cursortype;">Specifying a Cursor Type and Selecting Rows</link> 
          in the Microsoft SQLSRV documentation.</entry>
         </row>
        </tbody>
       </tgroup>
      </table>
     </listitem>
    </varlistentry>
   </variablelist>
  </para>
 </refsect1>
 
 <refsect1 role="returnvalues">
  &reftitle.returnvalues;
  <para>
   Returns a statement resource on success and &false; if an error occurred.
  </para>
 </refsect1>
 
 <refsect1 role="examples">
  &reftitle.examples;
  <para>
   <example>
    <title><function>sqlsrv_prepare</function> example</title>
    <para>
    This example demonstrates how to prepare a statement with <function>sqlsrv_prepare</function> 
    and re-execute it multiple times (with different parameter values) using <function>sqlsrv_execute</function>.
    </para>
    <programlisting role="php">
<![CDATA[
<?php
$serverName = "serverName\sqlexpress";
$connectionInfo = array( "Database"=>"dbName", "UID"=>"username", "PWD"=>"password");
$conn = sqlsrv_connect( $serverName, $connectionInfo);
if( $conn === false) {
    die( print_r( sqlsrv_errors(), true));
}

$sql = "UPDATE Table_1
        SET OrderQty = ?
        WHERE SalesOrderID = ?";

// Initialize parameters and prepare the statement. 
// Variables $qty and $id are bound to the statement, $stmt.
$qty = 0; $id = 0;
$stmt = sqlsrv_prepare( $conn, $sql, array( &$qty, &$id));
if( !$stmt ) {
    die( print_r( sqlsrv_errors(), true));
}

// Set up the SalesOrderDetailID and OrderQty information. 
// This array maps the order ID to order quantity in key=>value pairs.
$orders = array( 1=>10, 2=>20, 3=>30);

// Execute the statement for each order.
foreach( $orders as $id => $qty) {
    // Because $id and $qty are bound to $stmt1, their updated
    // values are used with each execution of the statement. 
    if( sqlsrv_execute( $stmt ) === false ) {
          die( print_r( sqlsrv_errors(), true));
    }
}
?>
]]>
    </programlisting>
   </example>
  </para>
 </refsect1>

 <refsect1 role="notes">
  &reftitle.notes;
  <para>
   When you prepare a statement that uses variables as parameters, the variables 
   are bound to the statement. This means that if you update the values of the 
   variables, the next time you execute the statement it will run with updated 
   parameter values. For statements that you plan to execute only once, use 
   <function>sqlsrv_query</function>.
  </para>
 </refsect1>
 
 <refsect1 role="seealso">
  &reftitle.seealso;
  <para>
   <simplelist>
    <member><function>sqlsrv_execute</function></member>
    <member><function>sqlsrv_query</function></member>
   </simplelist>
  </para>
 </refsect1>
</refentry>

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