performance - actions taken on establishing a connection

[detule]

Currently when determining the structure of the object tree for the connection, we call odbcConnectionCatalogs/Schemas just to verify if there is a non-trivial result. For example, if length(odbcConnectionSchemas(conn)) then <include schemas in object tree>.

We have seen instances where these catalog calls can be expensive. At the same, this information should be available by interrogating theSQL_CATALOG_NAME and SQL_SCHEMA_USAGE info types in the SQLGetInfo API call. Driver should be able to satisfy these calls without a round-trip to data source.