Significant core improvement
-possibility of processing sequence of queries as an atomic operation
-sequence is sent in transaction
-sequence can contain "IF" query with branching function to switch following query on or off
->paginate is much safer now
->upsert is much safer now
->upsert is implemented in 2 versions:one-query fast version for pg 9.1 and higher, query-sequence slow version for older pg versions
-client automatically gets the server version
-client automatically sellects proper version of the upsert

-unified returns of querying functions