Abstract: Optimizing query statements in relational databases including determining filtering performance for each of at least two complex predicates in a predetermined layer of the query statement based on a result of a query performed on predetermined data records by using only the complex predicate. The results are ranked based on the filtering performance and re-ordered so that a complex predicate with a higher filtering performance is ranked before a complex predicate with a lower filtering performance. These techniques produce shortened data query response times and improved execution efficiency.

Abstract: Systems for replication group partitioning include a workload profiling module configured to analyze historical workload data for a plurality of data elements to identify and categorize one or more transaction patterns; and a recommendation module configured to generate a recommended partitioning of the plurality of data elements into one or more replication groups, based on the one or more transaction patterns, that are optimized toward a partitioning goal.

Abstract: Embodiments relate to a system, computer program product and method for database query optimization. An aspect includes a method that extracts complex predicates from a query statement, the query statement having at least two complex predicates. The method then executes a query associated with the query statement and obtains at least a respective execution structure cost (?Ti) for each of the complex predicates. The method also calculates an overall execution structure cost corresponding to each of the complex predicates, the complex predicates being arranged according to result of the query and the execution structure costs (?Ti); and optimizes a database query by selecting the arrangement of complex predicates having a lowest overall execution structure cost.