Nested loops are a typical efficiency drawback in Oracle. They happen when a question has to loop by means of a desk a number of instances to get the info it wants. This may be very inefficient, particularly for big tables.
There are a variety of how to keep away from nested loops. A technique is to make use of indexes. Indexes are particular knowledge constructions that Oracle makes use of to hurry up queries. By creating an index on the column that’s being looped by means of, Oracle can rapidly discover the info it wants with out having to scan the whole desk.
