Description |
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| Adaptive Server IQ 12.4.0 | |
Description | For joins within a query, the IQ optimizer has a choice of several algorithms | |||
| for processing the join. This option allows you to override the optimizer’s | |||
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| internal rules that determine whether an algorithm is legal within the query | |||
| engine. If you set it to any | |||
| cannot be used to selectively modify one join out of several in a query. | |||
| This option is normally used for internal testing, and only experienced DBA's | |||
| should use it. The following table describes the valid values for this option and | |||
| their action. |
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| Value |
| Action | |
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| 0 |
| Let the optimizer choose | |
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| 1 |
| Prefer sort/merge | |
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| 2 |
| Prefer nested loop | |
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| 3 |
| Prefer nested loop | |
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| 4 |
| Prefer hash | |
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| 5 |
| Prefer hash | |
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| 6 |
| Prefer join index | |
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| Avoid sort/merge | ||
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| Avoid nested loop | ||
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| Avoid nested loop | ||
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| Avoid hash | ||
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| Avoid hash | ||
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| Avoid join index | ||
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9.4.7 Corrections to INSERT LOCATION
These corrections apply to the Adaptive Server IQ Reference Manual and the
Adaptive Server IQ Administration and Performance Guide.
If you plan to use the INSERT LOCATION command (syntax 3 of the INSERT command), the Adaptive Server Enterprise server you are connecting to must exist in the interfaces file on the local machine.
Also, the syntax in the Adaptive Server IQ Reference Manual is incorrect. The servername.dbname must be enclosed in single quotes, and the SELECT statement must be in braces. An example of correct syntax is:
INSERT CUSTOMERS LOCATION ’BOSTON.PUBS2’
32 | Release Bulletin for Digital UNIX |