How does Join Transitive Closure (JTC) differ from Search Argument (SARG) Transitive Closure?
As of release 11.0.1, Sybase has always had transitive closure for search arguments, but introduced join transitive closure in Adaptive Server 12. JTC allows the optimizer to consider a join order other than those made available explicitly by the query’s WHERE clause. Columns participating in joins created by JTC may have indexes that will result in more favorable query plans that those available on the columns of the explicitly stated joins. SARG transitive closure occurs with two or more tables involved in a join with the joining column part of a SARG. Join Transitive Closure occurs with three tables and infers a third join.
