Revisit `QueryEnhancer` exception handling

[mp911de]

For some queries (e.g. INSERT, UPDATE, DELETE), it doesn't make sense to derive count queries or apply sorting. We should throw proper exceptions instead of returning default values that do not make any sense.

[arefbehboudi]

@mp911de As a beginner in open-source contributions, do you think it's okay for me to start working on this issue?