You can create a condition that determines if the Integration Service updates the dynamic lookup cache. If the condition is false or NULL, the Integration Service does not update the dynamic lookup cache.
If the condition is false or NULL, regardless of the Lookup transformation properties, the NewLookupRow value is 0 and the Integration Services does not update the dynamic lookup cache with any row inserts or updates.
If the NewLookupRow value is 2, that is, the row is marked for update, and you enable Update Else Insert, the Integration Service performs one of the following:
If the row exists in the cache, the Integration Service updates the existing row in the cache.
If the row does not exist in the cache, the Integration Service inserts the new row in the cache.
If the NewLookupRow value is 1, that is, the row is marked for insert, and you enable Insert Else Update, the Integration Service performs one of the following:
If the row does not exist in the cache, the Integration Service inserts the new row in the cache.
If the row exists in the cache, the Integration Service updates the existing row in the cache.