This method is used to communicate an error and invoke error callbacks etc. Basically a wrapper for PEAR::raiseError without the message string.
DBA_Driver_Builtin uses the builtin dba functions of PHP as the underlying driver for a DBA class. Depending on the driver, this can be faster or slower than the DBA_Driver_File class.
This class has been tested with DB3 and GDBM and probably works with DB2. Other drivers may have quirks that this class does not address yet. CDB is known to be unsuitable as a driver due to its lack of write ability.
The mode in which to open a database. 'r' opens read-only. 'w' opens read-write. 'n' creates a new database and opens read-write. 'c' creates a new database if the database does not exist and opens read-write.
Determines whether to open the database peristently. Not supported here.