The DBcursor->c_get function is the standard function for retrieving
records from the database, with a cursor. In general, the cursor get
function takes a key and returns the associated data from the database.
There are several flags that you can set to customize retrieval:
Return the record from the database that matches both the supplied key
and data items. This is particularly useful when there are large numbers
of duplicate records for a key, as it allows the cursor to easily be
positioned at the correct place for traversal of some part of a large set
of duplicate records.