svn commit - mysqldoc@docsrva: r137 - branches/MikePluggable/trunk/refman-5.1

[eherman]

Author: eherman
Date: 2005-10-22 01:31:59 +0200 (Sat, 22 Oct 2005)
New Revision: 137

Log:
added a few comments from ha_partiton.h

Modified:
   branches/MikePluggable/trunk/refman-5.1/custom-engine.xml

Modified: branches/MikePluggable/trunk/refman-5.1/custom-engine.xml
===================================================================
--- branches/MikePluggable/trunk/refman-5.1/custom-engine.xml	2005-10-21 21:36:56 UTC (rev 136)
+++ branches/MikePluggable/trunk/refman-5.1/custom-engine.xml	2005-10-21 23:31:59 UTC (rev 137)
@@ -4643,7 +4643,7 @@
        <itemizedlist>
           <listitem>
            <para>
-             <literal></literal>
+             <literal>FALSE</literal> Success
            </para>
          </listitem>
        </itemizedlist>
@@ -6864,6 +6864,9 @@
        <title>Description</title>
 
     <para>This is the <function>keys_to_use_for_scanning</function> method.</para>
+        <para>This method is used to derive whether an index can be used for
+          index-only scanning when performing an ORDER BY query.
+          Only called from one place in sql_select.cc</para>
       </refsection>
 
       <refsection>
@@ -7887,6 +7890,9 @@
           </para><para>
           Called from handler.cc by handler::ha_open(). The server opens all tables by
           calling ha_open() which then calls the handler specific open().</para>
+        <para>A handler object is opened as part of its initialisation and before
+          being used for normal queries (not before meta-data changes always.)
+          If the object was opened it will also be closed before being deleted.</para>
       </refsection>
 
       <refsection>
@@ -8369,6 +8375,8 @@
         <para>This is never called for InnoDB or BDB tables, as these table types
           has the HA_NOT_EXACT_COUNT set.
         </para>
+        <para>read_first_row is virtual method but is only implemented by
+          handler.cc, no known storage engine overrides it.</para>
       </refsection>
 
       <refsection>
@@ -8787,7 +8795,7 @@
 
       <refnamediv>
         <refname>records_in_range</refname>
-        <refpurpose></refpurpose>
+        <refpurpose>For the given range how many records are estimated to be in this range.</refpurpose>
       </refnamediv>
 
       <refsynopsisdiv>
@@ -8809,7 +8817,10 @@
         <para>Given a starting key, and an ending key estimate the number of rows that
           will exist between the two. end_key may be empty which in case determine
           if start_key matches any rows.
-          </para><para>
+          </para>
+        <para>
+          Used by optimiser to calculate cost of using a particular index.</para>
+          <para>
           Called from opt_range.cc by check_quick_keys().</para>
       </refsection>
 
@@ -10119,6 +10130,8 @@
        <title>Description</title>
 
     <para>This is the <function>start_stmt</function> method.</para>
+        <para>When table is locked a statement is started by calling start_stmt
+          instead of external_lock</para>
       </refsection>
 
       <refsection>