sql - indexing queries in oracle -


i wrote query find number of purchases there @ least 1000 other purchases, if servicetype, gst , paymenttype same.

i thinking of adding index make query faster, thought bitmap index way go , create on servicetype, paymenttype , gst columns.

what best index speed query above?

thanks,

jim

b-tree indexes (default)

bitmap indexes : used when number of distinct values less used on tables less updated or not updated @ all.

reverse key indexes : used in rac prevent hotspots.

partitioned indexes (local / global). (local partitioned indexes use same partitioning scheme table using , global partitioned indexes can have different indexing scheme parent tables)

cluster indexes : created on clustered tables.


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