Except for Query,Insert,Delete,Update statement, we store other statement as PureStatement.
We separate them because PureStatement don’t have query and parameters (except
create-table-as, create-view-as, create-sink-as), so we don’t need to do extra work(infer and
bind parameter) for them.
For create-table-as, create-view-as, create-sink-as with query parameters, we can’t
support them. If we find that there are parameter in their query, we return a error otherwise we
store them as PureStatement.