Library Version 18.1.40

Db::set_priority()
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## Db::set_priority()

    #include <db_cxx.h>

    int
    Db::set_priority(DB_CACHE_PRIORITY priority);

Set the cache priority for pages referenced by the Db handle.

The priority of a page biases the replacement algorithm to be more or less likely to discard a page when space is needed in the buffer pool. The bias is temporary, and pages will eventually be discarded if they are not referenced again. The `Db::set_priority()` method is only advisory, and does not guarantee pages will be treated in a specific way.

When called on a database that has been opened with sliced support, the `Db::set_priority()` method is automatically called on each supporting slice database.

The `Db::set_priority()` method may be called at any time during the life of the application.

The `Db::set_priority()` method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success.

### Parameters

#### priority

The priority parameter must be set to one of the following values:

- `DB_PRIORITY_VERY_LOW`

  The lowest priority: pages are the most likely to be discarded.

- `DB_PRIORITY_LOW`

  The next lowest priority.

- `DB_PRIORITY_DEFAULT`

  The default priority.

- `DB_PRIORITY_HIGH`

  The next highest priority.

- `DB_PRIORITY_VERY_HIGH`

  The highest priority: pages are the least likely to be discarded.

### Class

Db

### See Also

Database and Related Methods

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