int DB->del(DB *db, DB_TXN *txnid, DBT *key, u_int32_t flags);
The DB->del method removes key/data pairs from the database. The key/data pair associated with the specified key is discarded from the database. In the presence of duplicate key values, all records associated with the designated key will be discarded.
When called on a database that has been made into a secondary index using the DB->associate method, the DB->del method deletes the key/data pair from the primary database and all secondary indices.
If the operation is to be transaction-protected (other than by specifying the DB_AUTO_COMMIT flag), the txnid parameter is a transaction handle returned from DB_ENV->txn_begin; otherwise, NULL.
The flags value must be set to 0 or the following value:
If the specified key is not in the database, the DB->del method will return DB_NOTFOUND. Otherwise, the DB->del method returns a non-zero error value on failure and 0 on success.
The DB->del method may fail and return a non-zero error for the following conditions:
The DB->del method may fail and return a non-zero error for errors specified for other Berkeley DB and C library or system functions. If a catastrophic error has occurred, the DB->del method may fail and return DB_RUNRECOVERY, in which case all subsequent Berkeley DB calls will fail in the same way.
Copyright Sleepycat Software