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Repository level Performance in Informatica

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Tuning Repository Performance


The PowerMart and PowerCenter repository has more than 80 tables and almost all tables use one or more indexes to speed up queries. Most databases keep and use column distribution statistics to determine which index to use to execute SQL queries optimally. Database servers do not update these statistics continuously.

In frequently-used repositories, these statistics can become outdated very quickly and SQL query optimizers may choose a less than optimal query plan. In large repositories, the impact of choosing a sub-optimal query plan can affect performance drastically. Over time, the repository becomes slower and slower.

To optimize SQL queries, you might update these statistics regularly. The frequency of updating statistics depends on how heavily the repository is used. Updating statistics is done table by table. The database administrator can create scripts to automate the task.

You can use the following information to generate scripts to update distribution statistics.


Note: All PowerMart/PowerCenter repository tables and index names begin with “OPB_”.
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