Cost-based optimizations for join queries with union all views and derived tables

A query having a Union All view is identified. A logical join between Union AH view/derived table and other tables is broken down into multiple physical joins. The physical joins are pushed to the branches. Cost-based processing statistics are obtained for the branches. An optimal plan for the joins...

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Hauptverfasser: Korlapati, Rama Krishna, Al-Kateb, Mohammed, Ma, Lu, Au, Grace Kwan-On, Nair, Sanjay
Format: Patent
Sprache:eng
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Zusammenfassung:A query having a Union All view is identified. A logical join between Union AH view/derived table and other tables is broken down into multiple physical joins. The physical joins are pushed to the branches. Cost-based processing statistics are obtained for the branches. An optimal plan for the joins is selected based on the statistics; representing an optimal query execution for the query. The optimal query execution plan is provided to a database engine for executing the optimal query execution plan against a data warehouse.