The Integration Service updates the dynamic cache based on the row type, query result, and the Lookup transformation properties.
When you use a dynamic lookup cache, define the row type of the rows entering the Lookup transformation as either insert or update. You can define some rows as insert and some as update, or all insert, or all update. By default, the row type of all rows entering a Lookup transformation is insert. You can add an Update Strategy transformation before the Lookup transformation to define the row type as update.
The Integration Service either inserts or updates rows in the cache, or does not change the cache. By default, the Lookup transformation inserts a row in the cache when the row type is insert, and updates a row when the row type is update.
However, you can configure the following Lookup properties to change how the Integration Service handles inserts and updates to the cache:
Insert Else Update
. Applies to rows entering the Lookup transformation where the row type is insert. Use this option to update the row in the cache if the data already exists in the cache. If you do not enable this option, the Integration Service inserts the rows into the cache regardless if they exist.
Update Else Insert
. Applies to rows entering the Lookup transformation where the row type is update. Use this option to insert an update row if the data does not exist in the cache. If you do not enable this option, the Integration Service ignores the row if it does not exist in the cache.
You can select either the Insert Else Update or Update Else Insert property, or you can select both properties or neither property.
You can configure the Lookup transformation to synchronize the Lookup source and the dynamic cache. When you synchronize the Lookup source and the cache, the Lookup transformation inserts rows directly in the Lookup source. You do not pass insert rows to the target. Use this configuration to run multiple sessions with Lookup transformations that insert rows to the same target.