The Informatica Server builds a cache in memory when it processes the first row of data in a cached Lookup transformation. The Informatica Server stores condition values in the index cache and output values in the data cache. The Informatica Server queries the cache for each row that enters the transformation.
- 1 What are the different types of cache in Informatica?
- 2 What are caches in Informatica?
- 3 How many cache files are created in Informatica?
- 4 Where is cache stored in Informatica?
- 5 What is static and dynamic cache in Informatica?
- 6 What is difference between stop and abort in Informatica?
- 7 What are the different types of caches?
- 8 What are the types of lookups?
- 9 What is persistent cache?
- 10 Can we delete cache files in Informatica?
- 11 How many types of lookups are there in Informatica?
- 12 What is database partitioning in Informatica?
- 13 What is incremental aggregation in Informatica?
- 14 What is the role of cache directory in mapping?
- 15 What is Joiner transformation?
What are the different types of cache in Informatica?
Types of Lookup Caches in Informatica
- Static cache: Static Cache is same as a Cached Lookup in which once a Cache is created and the Integration Service always queries the Cache instead of the Lookup Table.
- Dynamic cache:
- Shared cache:
- Persistent cache:
- Re-cache from database.
What are caches in Informatica?
When you run a mapping that uses an Aggregator, Joiner, Lookup, Rank, or Sorter transformation, the Data Integration Service creates caches in memory to process the transformation. If the Data Integration Service requires more space, it stores overflow values in cache files on disk.
How many cache files are created in Informatica?
When you run a session, the Integration Service creates at least one cache file for each transformation. If the Integration Service cannot process a transformation in memory, it writes the overflow values to the cache files.
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.
What is static and dynamic cache in Informatica?
Static Cache gets created once and reused through out the session. Dynamic Cache gets created initially and then data keep inserted/updated during the session. Dynamic cache option is useful when lookup table and target table are same and you have need to update data in cache.
What is difference between stop and abort in Informatica?
– STOP option allows the writing of the data and committing the data to the targets, whereas ABORT shows no commitment as such. – STOP option doesn’t kill any process and it just stops the resource sharing between the processes, whereas ABORT stops the process and the session gets terminated.
What are the different types of caches?
There is three types of cache:
- direct-mapped cache;
- fully associative cache;
- N-way-set-associative cache.
What are the types of lookups?
There are two forms of Lookup: Vector and Array. The vector form of the LOOKUP function will search one row or one column of data for a specified value and then get the data from the same position in another row or column.
What is persistent cache?
The Integration Framework uses a separate SQL repository to track integration information. This SQL repository is referred to as the persistent cache or the Integration Data repository. This property tracks whether the item in the local repository is up to date with the data in the remote system.
Can we delete cache files in Informatica?
idx files created in the $INFA_HOME/server/ infa_shared/Cache are deleted after the session execution. However, in some cases (such as when a session fails or terminates unexpectedly) these files may persist and become obsolete.
How many types of lookups are there in Informatica?
Lookup Cache can be of two types: 1. Dynamic Cache: If its Dynamic Cache then integration service takes the rows from the cache. This improves the session performance and speeds up the activity.
What is database partitioning in Informatica?
The partition type controls how the PowerCenter Integration Service distributes data among partitions at partition points. When we configure the partitioning information for a pipeline, then we must define a partition type at each partition point in the pipeline.
What is incremental aggregation in Informatica?
When using incremental aggregation, you apply captured changes in the source to aggregate calculations in a session. If the source changes incrementally and you can capture changes, you can configure the session to process those changes.
What is the role of cache directory in mapping?
A map cache represents a snapshot of your map at one point in time. Because of this, caches work best with maps that do not change frequently. These include street maps, imagery, and terrain maps.
What is Joiner transformation?
Joiner transformation is an active and connected transformation. It provides the option of creating joins in the Informatica. By using the joiner transformation, the created joins are similar to the joins in databases. The joiner transformation is used to join two heterogeneous sources.