feature request: new gloval_variable digest_use_lowercase

[btkador]

Normally hashes are case sensitive, but I'm not sure if it is supposed to be related to digest_text, since mysql doesn't care if statements are lower or upper case.

mysql> select digest,digest_text from stats_mysql_query_digest where digest_text 
like "select id from sample_table limit ?";

+--------------------+--------------------------------------+
| digest             | digest_text                          |
+--------------------+--------------------------------------+
| 0xE1612CA769ADE07E | SELECT id from sample_table limit ?  |
| 0x575A2061B1BCC5F0 | select id from sample_table limit ?  |
+--------------------+--------------------------------------+

How about a global variable like digest_use_lowercase which is default 0, but if set to 1 always convert digest_text to lowercase before creating the digest, to don't break compatibility with existing installations using the hash?

Otherwise rules on digest won't match if a user uses uppercase, while the rule was based on lowercase - so it's somehow related on #717 :-)

[renecannao]

Seems a valid feature request!
Thanks

[renecannao]

Commit d1b40f7 introduces new variable mysql-digests_lowercase, false by default.