Specifying Buffered Logging

The following example creates a database that uses a buffered log:
CREATE DATABASE vehicles WITH BUFFERED LOG; 
If transactions are made against a database that uses buffered logging, the transaction log records are held in a logical-log memory buffer for as long as possible. They are not flushed from this logical-log buffer in shared memory to the logical log on disk until one of the following situations occurs:
  • The buffer is full.
  • A transaction is committed on the database with unbuffered logging.
  • A checkpoint occurs.
  • The connection is closed.

If you use a buffered log, you marginally enhance the performance of logging at the risk of not being able to re-create the last few transactions after an assertion failure.

ANSI/ISO-compliant databases cannot support buffered logging, but must be created with the LOG MODE ANSI keywords:
CREATE IF NOT EXISTS DATABASE nobuficles WITH LOG MODE ANSI; 

See also the discussion of buffered logging in the Informix® Database Design and Implementation Guide.