13. A system comprising: an interface to receive first queries from a client system; one or more processors; and a software utility executable on the one or more processors to: establish plural sessions with a database system, each session associated with at least one transaction; identify transactions that operate on the same set of one or more tuples; re-allocate transactions between or among the sessions such that the identified transactions that operate on the same set of one or more tuples is allocated to one of the sessions; identify first queries of a particular one of the transactions that specify commutative and associative operations, and group the identified first queries into a second query.
14. The system of claim 13 , wherein the statements comprises Structured Query Language (SQL) statements.