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Adding Duplicate Copies of Tables

Duplicating some small, relatively static tables across all coservers can improve performance if queries require serial plans and all other data is on the same coserver.

To duplicate a table explicitly, use the CREATE DUPLICATE oF TABLE statement, as described in the IBM Informix: Guide to SQL Syntax.

In some DSS queries, the database server might automatically replicate a table smaller than 128 kilobytes that is involved in a hash join if such replication would improve performance. This feature is called small-table broadcast.

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