Berkeley DB Reference Guide: Access Methods
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Berkeley DB Reference Guide: Access Methods

Retrieving records

The DB->get function is the standard function for retrieving records from the database. In general, the get function takes a key and returns the associated data from the database.

There are a few flags that you can set to customize retrieval:

Search for a matching key and data item, i.e., only return if both the key and the data items match those stored in the database.

Acquire write locks instead of read locks during retrieval. This can enhance performance in threaded applications where deadlock is a concern.

If the underlying database is a Btree, and was configured so that it is possible to search it by logical record number, retrieve a specific record.

If the database has been configured to support duplicate records, DB->get will always return the first data item in the duplicate set.