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Background documentation Selects and Fetches Locate the document in the library structure

<number of> selects and fetches, selectivity <percentage>%: <number of> rows read, <number of> rows qualified

Explanation

The strategies for accessing table data are poor for SELECT or FETCH statements. The system has to read a large number of table rows to find a small number of rows that fulfill a WHERE condition.

User Response

Find the statement that causes this poor ratio of read rows to found rows, and check the access strategies for this statement.

Note

For information on creating optimized SQL statements, see the Structure linkSQL Optimizer documentation.

 

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