The cache is memory allocation for that instance in the server. The Integration Service builds a cache in memory when it processes the first row of data in a cached Lookup transformation. It allocates memory for the cache based on the amount you configure in the transformation or session properties.
Static cache: The cache that cannot be changed through the session. It caches the lookup file or table and looks up values in the cache for each row that comes into the transformation. When the lookup condition is true, the Integration Service returns a value from the lookup cache. The Integration Service does not update the cache while it processes the Lookup transformation. By default the Integration Service creates a static cache and it read only.
Dynamic cache: The cache that can be changed through the session. The Integration Service dynamically inserts or updates data in the lookup cache and passes the data to the target. The dynamic cache is synchronized with the target. To cache a table, flat file, or source definition and update the cache, configure a Lookup transformation with dynamic cache.
Shared cache: The cache which can be used between multiple transformations. A named cache can be used more than one place within the same mapping. A unnamed cache can be used more than one or more places within mapping or different mappings.
Pre-build lookup cache: When you configured for sequential caches, the Integration Service creates caches as the source rows enter the Lookup transformation. When you configure the session to build concurrent caches, the Integration Service does not wait for the first row to enter the Lookup transformation before it creates caches. Instead, it builds multiple caches concurrently.
named cache:
When you want to share a persistent cache file across mappings then they it will be named and that can be used. The caching structures must match or be compatible with a named cache. It can share static and dynamic named caches.
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Types of cache:
Persistent cache: Once save the lookup cache files and reuse them the next time the Integration Service processes a Lookup transformation configured to use the cache.
Re-cache from lookup source: If the persistent cache is not synchronized with the lookup table, you can configure the Lookup transformation to rebuild the lookup cache.Static cache: The cache that cannot be changed through the session. It caches the lookup file or table and looks up values in the cache for each row that comes into the transformation. When the lookup condition is true, the Integration Service returns a value from the lookup cache. The Integration Service does not update the cache while it processes the Lookup transformation. By default the Integration Service creates a static cache and it read only.
Dynamic cache: The cache that can be changed through the session. The Integration Service dynamically inserts or updates data in the lookup cache and passes the data to the target. The dynamic cache is synchronized with the target. To cache a table, flat file, or source definition and update the cache, configure a Lookup transformation with dynamic cache.
Shared cache: The cache which can be used between multiple transformations. A named cache can be used more than one place within the same mapping. A unnamed cache can be used more than one or more places within mapping or different mappings.
Pre-build lookup cache: When you configured for sequential caches, the Integration Service creates caches as the source rows enter the Lookup transformation. When you configure the session to build concurrent caches, the Integration Service does not wait for the first row to enter the Lookup transformation before it creates caches. Instead, it builds multiple caches concurrently.
named cache:
When you want to share a persistent cache file across mappings then they it will be named and that can be used. The caching structures must match or be compatible with a named cache. It can share static and dynamic named caches.
Thanks
Ur's Hari
If you like this post, please share it by clicking on g+1 Button.
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