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About PSP Cache
Siebel PSP Cache is a mechanism designed to improve performance of PSP transforms. PSP Look-Up transforms use caching to reduce the number of SQL statements executed by the database. The cache stores the results of PSP Look-Up transform queries. The cache key is the business object, the business component, the search specification, and the sort specification.
The PSP Cache of query results is shared across all user sessions on an Object Manager. A particular query is issued only once for each Object Manager and then shared by all users. This sharing maximizes the probability of a cache hit and improves performance and scalability for all users on the server.
Transforms Involving Database Queries
Of all the PSP methods (transforms) provided by the Row Set Transformation Toolkit business service, those that involve database queries are the following:
- Simple Look-Up
- Hierarchical Look-Up
- Rule Set Look-Up
- Dynamic Look-Up
There are two ways that PSP Cache is implemented: one is special for the Dynamic Look-Up transform, and the other is for the rest of the transforms:
The following topics contain more information about PSP Cache: