What is cache and Uncached lookup in Informatica?

If the lookup is cache(By default static cache) Informatica server builds the cache when it processes the first lookup request .But when it is. uncached lookup it queries the lookup source(direct to the Database) instead of building and querying the cache.

What is cached lookup in Informatica?

When a lookup is cached: Informatica queries the database, brings the whole set of rows to the Informatica server and stores in a cache file. When this lookup is called next time, Informatica uses the file cached. As a result, Informatica saves the time and the resources to hit the database again.

Where is cache stored in Informatica?

The Integration Service creates the cache files by default in the $PMCacheDir directory. If the Integration Service process does not find the directory, it fails the session and writes a message to the session log indicating that it could not create or open the cache file.

Which lookup is better in Informatica?

Unconnected Lookup is always better.. It takes less time as compared to that of Connected Lookup. Because Unconnected Transformation is Isolated within the mapping,we can call this lookup with the help of a Expression transformation. Where as connected loopup is connected in a single pipeline from source to target.

What type of cache give performance benefit in lookup?

Persistent cache
Persistent cache gives you performance boost by saving time in building the lookup while session run but it still takes the same time like a normal lookup for using the lookup data during session runtime.

What happens when lookup caching is disabled?

When you disable caching, each time a row passes into the transformation, the Informatica Server issues a select statement to the lookup table for lookup values. Indicates whether the Lookup transformation caches lookup values during the session.

What is the default cache in Informatica?

By default, the memory cache for a transformation is set to auto mode. The Integration Service automatically allocates cache memory to all transformations that have their caches set to auto mode. You can set the maximum amount of cache memory that the Integration Service can allocate to the transformations.

Which cache will be deleted immediately in Informatica?

Persistent cache – the permanent one By default, the cache is created as non-persistent, that is, the cache will be deleted once the session run is complete.

How dynamic lookup cache works in Informatica?

If the cache is dynamic, the task updates the cache based on the actions in the task, so if the task uses the lookup multiple times, downstream transformations can use updated data. You can use a dynamic cache with most types of lookup sources. You cannot use a dynamic cache with flat file or Salesforce lookups.