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Parameter type
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Integer
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Default value
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If OPTIMIZER_FEATURES_ENABLE is set to 9.0.0 or higher, then 2000
If OPTIMIZER_FEATURES_ENABLE is set to 8.1.7 or lower, then 80000
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Parameter class
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Dynamic: ALTER SESSION
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Range of values
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4 to 80000
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OPTIMIZER_MAX_PERMUTATIONS restricts the number of permutations of the tables the optimizer will consider in queries with joins. Such a restriction ensures that the parse time for the query stays within acceptable limits. However, a slight risk exists that the optimizer will overlook a good plan it would otherwise have found.
The default value for this parameter is 80000, which corresponds to no limitation at all. Setting this parameter to a value less than 1000 normally ensures parse times of a few seconds or less.
