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Toad® Papers and Podcasts
Training Resources |
Secrets of the SQL Optimizer
A Toad® for Oracle Tech Brief, by Richard To
The SQL Optimizer provides a solution for improving SQL statement performance that an internal database management system’s SQL optimizer cannot provide. For years, commercial database manufacturers have fought an endless battle to improve the performance of inserting, updating, deleting and retrieving information stored in the database. Despite their ongoing efforts and hard work, we have not seen a significant improvement in the performance of most Relational Database Management Systems (RDBMS). Users still suffer from under-performing SQL statements, and database experts are still spending countless hours tuning SQL statements.
Major deficiencies cause the database’s internal SQL optimizer to fail to find a good execution plan for a SQL statement. Two of these deficiencies include inaccurate database statistics and SQL cost estimation of the resources that may be used for the SQL statement.
PDF Document, 920 KB
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