Dynamic lookup cache not updating
Here in this article we will concentrate on different approaches to generate Surrogate Key for different type ETL process.
We discussed about Surrogate Key in in detail in our previous article.
Metadata is stored in a global metadata repository, enabling data lineage functionality.
Tuning a Power Center 8 ETL environment is not that straightforward. There are four crucial domains that require attention: system, network, database and the Power Center 8 installation itself.
The Lookup transformation returns the result of the lookup to the target or another transformation. We can configure the Lookup transformation to one of the following types of lookups: 1. a) We can override the default SQL statement if we want to add a WHERE clause or query multiple tables. When you create a Lookup transformation, you can create the lookup source from the following locations: - Relational source or target definition in the repository - Flat file source or target definition in the repository - Table or file that the Integration Service and Power Center Client machine can connect to - Source qualifier definition in a mapping 2. Lookup Properties Configure the lookup properties such as caching and multiple matches on the Lookup Properties tab. Lookup Condition The Integration Service finds data in the lookup source with a lookup condition.
You can configure the Lookup transformation to return a single row or multiple rows. Get a related value : Retrieve a value from the lookup table based on a value in the source. b) We can use a dynamic lookup cache with relational lookups. Flat File Lookup: When we use a flat file for a lookup source, we can use any flat file definition in the repository, or we can import it. Pipeline Lookup : When we use SAP application as lookup source in that case we use pipeline lookup. Configure the lookup condition or the SQL statements to query the lookup table. The lookup condition is similar to the WHERE clause in an SQL query.