Reverted 0bf2dadd: it's very common to use lower case for column types and upper case for other DB keywords.

` is a MySQL thing supported by cubrid. " is more common.

More request method checks

Zend Data Cache returns null when record doesn't exist (reverted from commit 590121c4)

Update single row query function

Fixed the issue that Object/Component doesn't support using anonymous function as normal property values.

[WIP] Cubrid db support