MySQL Bugs: #61947: Manual section 16.5.3 incorrect on partition pruning

Bug #61947	Manual section 16.5.3 incorrect on partition pruning
Submitted:	21 Jul 2011 21:53	Modified:	24 Aug 2011 8:32
Reporter:	Chris Wagner	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Server: Documentation	Severity:	S3 (Non-critical)
Version:	5.5+	OS:	Any
Assigned to:	Jon Stephens	CPU Architecture:	Any
Tags:	documentation, manual, Partition pruning, partitioning function

Description:
Section 16.5.3 of the 5.5 manual has wrong information about partition pruning.  It should state that the referenced time functions are only valid for pruning if the partitioned column is of type DATE or DATETIME.

--quote--
In MySQL 5.5, partition pruning is supported only for the TO_DAYS(), TO_SECONDS(), and YEAR() functions. In addition, beginning with MySQL 5.5.15, UNIX_TIMESTAMP() is treated as monotonic in partitioning expressions. See Section 16.4, “Partition Pruning”, for more information. 
--end quote--

http://dev.mysql.com/doc/refman/5.5/en/partitioning-limitations-functions.html
http://dev.mysql.com/doc/refman/5.5/en/partitioning-pruning.html

How to repeat:
n/a

Suggested fix:
fix verbiage.

Also, DIV should be listed as one of the allowed functions.  It is currently ommitted but stated elsewhere in the manual.

Looks like http://dev.mysql.com/doc/refman/5.5/en/partitioning-limitations-functions.html should be clarified.

DIV is not a function.

But http://dev.mysql.com/doc/refman/5.5/en/partitioning-pruning.html already states,

"Pruning can also be applied for tables partitioned on a DATE or DATETIME column when the partitioning expression uses the YEAR() or TO_DAYS() function."

DIV is not a "function" but it is an "operator".  The sections dealing with partition pruning are in need of organization and clarity.  In practice, functions and operators are used together and thus should be discussed together.

And besides, the statement "In MySQL 5.5, partition pruning is supported only for the TO_DAYS(), TO_SECONDS(), and YEAR() functions" is factually wrong since it states right above that that other functions are supported.

I missed the emphasis on "only" in the original report.

Fixed/closed.

-----

Author: js221926
Date: 2011-08-24 10:29:15 +0200 (Wed, 24 Aug 2011)
New Revision: 27143

Log:

Removed "only" - BUG#61947

Modified:
   trunk/refman-5.5/partitioning.xml
   trunk/refman-5.6/partitioning.xml

Modified: trunk/refman-5.5/partitioning.xml
===================================================================
--- trunk/refman-5.5/partitioning.xml	2011-08-24 08:19:36 UTC (rev 27142)
+++ trunk/refman-5.5/partitioning.xml	2011-08-24 08:29:15 UTC (rev 27143)
Changed blocks: 1, Lines Added: 2, Lines Deleted: 2; 731 bytes

@@ -6918,8 +6918,8 @@
       </informaltable>
 
       <para>
-        In MySQL &current-series;, partition pruning is supported only
-        for the <literal role="func">TO_DAYS()</literal>,
+        In MySQL &current-series;, partition pruning is supported for
+        the <literal role="func">TO_DAYS()</literal>,
         <literal role="func">TO_SECONDS()</literal>, and
         <literal role="func">YEAR()</literal> functions. In addition,
         beginning with MySQL 5.5.15,

Modified: trunk/refman-5.6/partitioning.xml
===================================================================
--- trunk/refman-5.6/partitioning.xml	2011-08-24 08:19:36 UTC (rev 27142)
+++ trunk/refman-5.6/partitioning.xml	2011-08-24 08:29:15 UTC (rev 27143)
Changed blocks: 1, Lines Added: 2, Lines Deleted: 2; 730 bytes

@@ -7973,8 +7973,8 @@
       </informaltable>
 
       <para>
-        In MySQL &current-series;, partition pruning is supported only
-        for the <literal role="func">TO_DAYS()</literal>,
+        In MySQL &current-series;, partition pruning is supported for
+        the <literal role="func">TO_DAYS()</literal>,
         <literal role="func">TO_SECONDS()</literal>, and
         <literal role="func">YEAR()</literal> functions. In addition,
         beginning with MySQL 5.6.3,