The parameterised prefetch path threshold. This threshold is used to determine when the prefetch path logic should switch to a subquery or when it should use a WHERE field IN (value1, value2, ... valueN) construct, based on the # of elements in the parent collection. If that # of elements exceeds this threshold, a subquery is constructed, otherwise field IN (value1, value2, ...) construct is used. The default value is 50. On average, this is faster than using a subquery which returns 50 elements. Use this to tune prefetch path fetch logic for your particular needs.

This threshold is also used to determine if paging is possible. A page size bigger than this threshold will disable the paging functionality when using paging + prefetch paths.