Cache Partitioning for Lookups
Cache partitioning creates a separate cache for each partition that processes an Aggregator, Joiner, Rank, or Lookup transformation. Cache partitioning increases mapping performance because each partition queries a separate cache in parallel.
When the Integration Service creates partitions for a mapping, it might use cache partitioning for partitioned Lookup transformations.
The Integration Service uses cache partitioning for connected Lookup transformations when the following conditions are true:
- •The lookup condition contains only equality operators.
- •When the connected Lookup transformation looks up data in a relational table, and the database is configured for case-sensitive comparison.
The Integration Service does not use cache partitioning for unconnected Lookup transformations.
When the Integration Service does not use cache partitioning for a Lookup transformation, all partitions of the Lookup transformation share the same cache. Each partition queries the same cache serially.