DB->del(DB *db, DB_TXN *txnid, DBT *key, u_int32_t flags);
The DB->del function 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.
If the file is being accessed under transaction protection, the
txnid parameter is a transaction ID returned from
txn_begin, otherwise, NULL.
The flags parameter is currently unused, and must be set to 0.
The DB->del function returns a non-zero error value on failure, 0 on success, and DB_NOTFOUND if the specified key did not exist in
The DB->del function may fail and return a non-zero error for the following conditions:
The operation was selected to resolve a deadlock.
An attempt was made to modify a read-only database.
An invalid flag value or parameter was specified.
The DB->del function 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 function may fail and return
DB_RUNRECOVERY, in which case all subsequent Berkeley DB calls will fail
in the same way.