菅原です。

> > 　菅原です。
> > 　少なくともこちらではoptimize tableしても同じ値を返しますけど……。
> 実行したSQLは下記の通りです。
> サーバのバージョンはMySQL 3.23.43です。

　とのことでしたので更新履歴を見てみましたら

> F.2.5 Changes in release 3.23.45
> 
> (UPDATE|DELETE) ...WHERE MATCH bugfix
> shutdown should now work on Darwin (Mac OS X).
> Fixed core-dump when repairing corrupted packed MyISAM files.
> --core-file now works on Solaris.
> Fix a bug which could cause InnoDB to complain if it cannot find free 
> blocks from the buffer cache during recovery.
> Fixed bug in InnoDB insert buffer B-tree handling that could cause 
> crashes.
> Fixed bug in InnoDB lock timeout handling.
> Fixed core dump bug in ALTER TABLE on a TEMPORARY InnoDB table.
> Fixed bug in OPTIMIZE TABLE that reset index cardinality if it was up 
> to date.
> Fixed problem with t1 LEFT_JOIN t2 ... WHERE t2.date_column IS NULL 
> when date_column was declared as NOT NULL.
> Fixed bug with BDB tables and keys on BLOB's.
> Fixed bug in MERGE tables on OS with 32 bit file pointers.
> Fixed bug in TIME_TO_SEC() when using negative values.

とありました。
　サーバの更新をしましょう :)

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菅原はじめ＠ホビー・データ
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