Difference between static and dynamic cache
In Informatica, caching mechanisms are used in lookup to improve performance by storing data temporarily in memory. There are two types of cache options for lookup: static and dynamic. Here’s a detailed comparison between the two:
Contents
| Static Cache | Dynamic Cache |
| 1. Definition: A static cache is populated once at the start of the session and remains unchanged throughout the session. Any changes made to the source or target data are not reflected in the cache. | 1. Definition: A dynamic cache is updated as the session runs. If a row is not found in the cache, it can be inserted or updated based on the session configuration. |
| 2. Use Case: Used when the lookup data remains constant and does not change during the session. Suitable for scenarios where the lookup table does not need to be updated frequently. | 2. Use Case: Used when the lookup data can change during the session, and those changes need to be reflected in the lookup. Suitable for scenarios where the lookup table needs to be frequently updated. |
| 3. Performance: Faster for scenarios where data does not change because it avoids the overhead of updating the cache during the session. | 3. Performance: May be slower than static cache due to the overhead of maintaining and updating the cache during the session. |
| 4. Behavior: Does not allow for updates or inserts into the cache. It only reads the data that was cached at the start. | 4. Behavior: Allows for inserts and updates into the cache. It can modify the cache based on the incoming data, ensuring the lookup data is always current. |
| 5. Typical Usage: Ideal for lookups on reference data or dimension tables that do not change often, such as country codes, product categories, etc. | 5. Typical Usage: Ideal for lookups on slowly changing dimensions (SCDs) or any scenarios where the lookup table data is expected to change during the ETL process. |
Practical Example : static and dynamic cache Informatica
| Static Cache | Dynamic Cache |
| – Static Cache: You are processing transaction data and need to look up product details from a product table. If the product table is static and does not change frequently, you can use a static cache. This way, the lookup will be faster since the data is loaded once and remains unchanged. | – Dynamic Cache: You are processing customer data and need to look up and update customer details in a customer table. If new customers can be added, or existing customer details can change during the session, you should use a dynamic cache. This ensures that any changes to the customer data are immediately reflected in the lookup cache, maintaining data integrity. |
| – Static Cache: Suitable for unchanging lookup data, faster performance, no updates during the session. | – Dynamic Cache: Suitable for frequently changing lookup data, can be updated during the session, may have slower performance due to maintenance overhead. |
Also Read :
1. What is the difference between Informatica PowerCenter and Informatica Cloud?
2.What is a Synchronization task in Informatica?
3.What is a Runtime environment in Informatica?
4.What is Check In Check Out in Informatica powercenter (Versioning)
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