sql.py: _query_lookup(): Fixed bug where params was cast to a tuple, even though it could also be a dict. index_cols(): Changed to use the connection-wide caching mechanism rather than its own custom cache.
sql.py: _query_lookup(): Fixed bug where params was cast to a tuple, even though it could also be a dict. index_cols(): Changed to use the connection-wide caching mechanism rather than its own custom cache.