svn commit - mysqldoc@docsrva: r5734 - in trunk: . refman-5.1

[paul]

Author: paul
Date: 2007-04-04 17:18:28 +0200 (Wed, 04 Apr 2007)
New Revision: 5734

Log:
 r18669@frost:  paul | 2007-04-04 10:16:51 -0500
 Prepared statements can use the query cache now, sometimes. (Bug#735)


Modified:
   trunk/refman-5.1/apis-c.xml
   trunk/refman-5.1/dba-core.xml
   trunk/refman-5.1/news-5.1.xml
   trunk/refman-5.1/sql-syntax.xml

Property changes on: trunk
___________________________________________________________________
Name: svk:merge
   - 4767c598-dc10-0410-bea0-d01b485662eb:/mysqldoc-local/mysqldoc/trunk:22867
7d8d2c4e-af1d-0410-ab9f-b038ce55645b:/mysqldoc-local/mysqldoc:18659
b5ec3a16-e900-0410-9ad2-d183a3acac99:/mysqldoc-local/mysqldoc/trunk:14218
bf112a9c-6c03-0410-a055-ad865cd57414:/mysqldoc-local/mysqldoc/trunk:14593
   + 4767c598-dc10-0410-bea0-d01b485662eb:/mysqldoc-local/mysqldoc/trunk:22867
7d8d2c4e-af1d-0410-ab9f-b038ce55645b:/mysqldoc-local/mysqldoc:18669
b5ec3a16-e900-0410-9ad2-d183a3acac99:/mysqldoc-local/mysqldoc/trunk:14218
bf112a9c-6c03-0410-a055-ad865cd57414:/mysqldoc-local/mysqldoc/trunk:14593


Modified: trunk/refman-5.1/apis-c.xml
===================================================================
--- trunk/refman-5.1/apis-c.xml	2007-04-04 13:59:00 UTC (rev 5733)
+++ trunk/refman-5.1/apis-c.xml	2007-04-04 15:18:28 UTC (rev 5734)
Changed blocks: 1, Lines Added: 3, Lines Deleted: 3; 724 bytes

@@ -12359,9 +12359,9 @@
 
       <listitem>
         <para>
-          <emphasis>Prepared statements do not use the query cache, even
-          in cases where a query does not contain any
-          placeholders</emphasis>. See
+          Before MySQL 5.1.17, prepared statements do not use the query
+          cache. As of 5.1.17, prepared statements use the query cache
+          under the conditions described in
           <xref linkend="query-cache-how"/>.
         </para>
       </listitem>


Modified: trunk/refman-5.1/dba-core.xml
===================================================================
--- trunk/refman-5.1/dba-core.xml	2007-04-04 13:59:00 UTC (rev 5733)
+++ trunk/refman-5.1/dba-core.xml	2007-04-04 15:18:28 UTC (rev 5734)
Changed blocks: 2, Lines Added: 60, Lines Deleted: 6; 3412 bytes

@@ -30659,22 +30659,23 @@
         different queries and are cached separately.
       </para>
 
+<!-- commenting this out until I figure out how to revise the
+"before parsing" part, which is not true for prepared statements.
       <para>
         Because comparison of a query against those in the cache occurs
         before parsing, the cache is not used for queries of the
         following types:
       </para>
+-->
 
+      <para>
+        The cache is not used for queries of the following types:
+      </para>
+
       <itemizedlist>
 
         <listitem>
           <para>
-            Prepared statements
-          </para>
-        </listitem>
-
-        <listitem>
-          <para>
             Queries that are a subquery of an outer query
           </para>
         </listitem>

@@ -30735,6 +30736,59 @@
       </para>
 
       <para>
+        Before MySQL 5.1.17, prepared statements do not use the query
+        cache. As of 5.1.17, prepared statements use the query cache
+        under certain conditions, which differ depending on the
+        preparation method:
+      </para>
+
+      <itemizedlist>
+
+        <listitem>
+          <para>
+            Statements that are issued via the binary protocol using
+            <literal>mysql_stmt_prepare()</literal> and
+            <literal>mysql_stmt_execute()</literal>. See
+            <xref linkend="c-api-prepared-statements"/>.
+          </para>
+
+          <para>
+            For a prepared statement executed via the binary protocol,
+            comparison with statements in the query cache is based on
+            the text of the statement after expansion of
+            <literal>?</literal> parameter markers. The statement is
+            compared only with other cached statements that were
+            executed via the binary protocol. That is, for query cache
+            purposes, statements issued via the binary protocol are
+            distinct from statements issued via the text protocol.
+          </para>
+        </listitem>
+
+        <listitem>
+          <para>
+            Statements that are issued via the text (non-binary)
+            protocol using <literal>PREPARE</literal> and
+            <literal>EXECUTE</literal>. See <xref linkend="sqlps"/>.
+            These are denoted SQL PS statements here.
+          </para>
+
+          <para>
+            For a prepared statement executed via
+            <literal>PREPARE</literal> and
<literal>EXECUTE</literal>,
+            it is not cached if it contains any <literal>?</literal>
+            parameter markers. In that case, the statement after
+            parameter expansion contains references to user variables,
+            which prevents caching, even for non-prepared statements. If
+            the statement contains no parameter markers, the statement
+            is compared with statements in the query cache that were
+            executed via the text protocol (that is, it is compared with
+            other SQL PS statements and non-prepared statements).
+          </para>
+        </listitem>
+
+      </itemizedlist>
+
+      <para>
         A query cannot be cached if it contains any of the functions
         shown in the following table:
       </para>


Modified: trunk/refman-5.1/news-5.1.xml
===================================================================
--- trunk/refman-5.1/news-5.1.xml	2007-04-04 13:59:00 UTC (rev 5733)
+++ trunk/refman-5.1/news-5.1.xml	2007-04-04 15:18:28 UTC (rev 5734)
Changed blocks: 1, Lines Added: 8, Lines Deleted: 0; 713 bytes

@@ -522,6 +522,14 @@
 
       <listitem>
         <para>
+          Prepared statements now use the query cache under the
+          conditions described in <xref linkend="query-cache-how"/>.
+          (Bug #735)
+        </para>
+      </listitem>
+
+      <listitem>
+        <para>
           Added the <option>--secure-file-priv</option> option for
           <command>mysql-test-run.pl</command>, which limits the effect
           of the <literal>load_file</literal> command for


Modified: trunk/refman-5.1/sql-syntax.xml
===================================================================
--- trunk/refman-5.1/sql-syntax.xml	2007-04-04 13:59:00 UTC (rev 5733)
+++ trunk/refman-5.1/sql-syntax.xml	2007-04-04 15:18:28 UTC (rev 5734)
Changed blocks: 1, Lines Added: 6, Lines Deleted: 0; 563 bytes

@@ -25288,6 +25288,12 @@
       characters).
     </para>
 
+    <para>
+      Before MySQL 5.1.17, prepared statements do not use the query
+      cache. As of 5.1.17, prepared statements use the query cache under
+      the conditions described in <xref linkend="query-cache-how"/>.
+    </para>
+
   </section>
 
 </chapter>