Under uncommitted access, Essbase locks blocks for write access until Essbase finishes updating the block. Under committed access, Essbase holds locks until a transaction completes.With uncommitted access, blocks are released more frequently than with committed access. The essbase performace is better if we set uncommitted access. Besides, parallel calculation only works with uncommitted access.
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Database performance:
Uncommitted access always yields better database performance than committed access. When using uncommitted access, Essbase does not create locks that are held for the duration of a transaction but commits data based on short-term write locks.
Data consistency: Committed access provides a higher level of data consistency than uncommitted access. Retrievals from a database are more consistent. Also, only one transaction at a time can update data blocks when the isolation level is set to committed access. This factor is important in databases where multiple transactions attempt to update the database simultaneously.
Data concurrency:
Uncommitted access provides better data concurrency than committed access. Blocks are released more frequently than during committed access. With committed access, deadlocks can occur.
Database rollbacks:
If a server crash or other server interruption occurs during active transactions, the Essbase kernel rolls back the transactions when the server is restarted. With committed access, rollbacks return the database to its state before transactions began. With uncommitted access, rollbacks may result in some data being committed and some data not being committed.
