ANSI_QUOTES
The double quote character is interpreted as an identifier-quoting character.
IGNORE_SPACE
Ignore spaces after function names.
ERROR_FOR_DIVISION_BY_ZERO
The default is that MySQL returns NULL rather than a warning (or an error in strict mode.)
STRICT_TRANS_TABLES, STRICT_ALL_TABLES
Switching on 'strict mode.' STRICT_TRANS_TABLES is only for transactional tables.
TRADITIONAL
strict modes plus several additional restrictions.
ANSI
enables behaviors are more like ANSI SQL (ex. ANSI_QUOTES, PIPES_AS_CONCAT)
*SHOW WARNINGS shows MySQL warnings.