After optimization and execution testing, you may discover that the performance of the optimized SQL statements is still not satisfactory. To remedy this, first check that the searching quota has not been reached in the Optimization Details window. If it has, then you should increase the intelligence level or optimization options in the Options window and optimize again to ensure all transformed SQL statements are given. Rerun the SQL statement optimization after the review.
You can also review the access plan of the optimized SQL statement to check if there should be any alterations to the database structure such as adding a new index. The Index Expert module is used to generate alternative Index Sets for a SQL statement.
The following SQL Functions are available in the SQL Optimizer window to retrieve the access plan, the run time, result set and to convert parameter markers:
Run Result (SQL alternatives only)
Below is a list of available functions within the SQL Optimizer window.
These functions are available only for the original SQL statement <Edit SQL> when displayed in the editable SQL Text window.
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Button or Menu |
Function |
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SQL Menu
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SQL Menu
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SQL Menu
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File Menu |
These functions are available for original SQL and its alternatives.
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Button or Menu |
Function |
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SQL Menu
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SQL Menu
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SQL Menu
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Right-click Menu |
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SQL Menu |
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File Menu |
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SQL Menu
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SQL & Right-click Menu
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Right-click Menu |
These functions are available only after the original SQL statement has been rewritten or virtual indexes have been generated.
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Button or Menu |
Function |
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SQL Menu
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SQL Menu |
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Search Menu |
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Navigate Menu |
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Report Menu |
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View Menu |
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View Menu |
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View Menu |
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View Menu |
Quest SQL Optimizer for IBM® DB2® LUW maximizes SQL performance by automating the manual, time-intensive and uncertain process of ensuring that SQL statements are performing as fast as possible. SQL Optimizer analyzes, rewrites, and evaluates SQL statements within multiple database objects, files. With SQL Optimizer, you can analyze and optimize all your problem SQL from multiple sources. SQL Optimizer also provides you a complete index optimization and plan change analysis solution, from index recommendations to simulated index impact analysis, through comparison of multiple SQL access plans.
SQL Optimizer provides you with the following main modules.
SQL Optimizer (including SQL Rewrite and Generate Indexes functions)