Knowledgebase

Transaction-Controlled Files

An application can use FairCom DB’s transaction capabilities to guarantee atomicity and, optionally, recoverability of data. FairCom DB supports the following transaction processing options:

• PREIMG (provides atomicity without recoverability)
• TRNLOG (provides atomicity with recoverability)
• TRNLOG with LOGIDX indexes (provides atomicity with recoverability, with logging of index reorganization operations to speed automatic recovery).

The application selects the transaction processing options that are in effect for the file when it creates data and index files using FairCom DB file creation API functions. The following sections discuss the properties of each transaction processing option, including their effect on the state of files in the event of an abnormal server termination.

In This Section PREIMG Transaction Files TRNLOG Transaction Files TRNLOG Transaction Files with LOGIDX Indexes Delayed Durability 6-Byte Transaction Numbers