The selection of a proper set of indexes can improve database performance. The SQL Anywhere Index Consultant helps you select indexes by providing recommendations on the best set of indexes for your database.

You can run the Index Consultant against a single query by using Interactive SQL, or against the database by using Application Profiling mode in Sybase Central. When analyzing a database, the Index Consultant uses a tracing session to gather data and make recommendations. To see which indexes lead to improved execution plans, the Index Consultant estimates query execution costs using those indexes. It also evaluates multiple column indexes, single-column indexes, and investigates the impact of clustered or unclustered indexes.

The Index Consultant analyzes a database or single query by generating candidate indexes and determining their effect on performance. To explore the effect of different candidate indexes, the Index Consultant repeatedly re-optimizes the queries under different sets of indexes. It does not execute the queries.

You can analyze any reported errors encountered while running the Index Consultant by looking at the sql_code and log_message columns in the "DBO"."ix_consultant_log" table.

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