Uses for a Dynamic Lookup Cache
You can configure a Lookup transformation with a dynamic lookup cache to update the cache based on changes in the lookup source.
You might use a dynamic lookup cache for the following reasons:
- Update a master customer table with new and updated customer information.
- For example, you can use a Lookup transformation to perform a lookup on the customer table to determine if a customer exists in the target. The cache represents the customer table. The Lookup transformation inserts and update rows in the cache as it passes rows to the target.
- Use an exported flat file as a lookup source instead of a relational table.
- If the connection to the database is slow, you can export the relational table contents to a flat file and use the file as a lookup source. For example, you might need to use this method if an ODBC connection to a database is slow. You can configure the database table as a relational target in the mapping and pass the lookup cache changes back to the database table.