Now lets look at some advanced level terms of DB2 product. First comes Buffer Pool which is an extremely useful object for tuning DB2 performance. In fact Buffer Pool is just a region of memory where database keeps indexes and data. Initially pools are small. So it’s a rule of thumb to always tune them during database installation.
Next one is Transaction Logs. Transaction Logs are of big importance to any database. They keep track of transactions happening in database and in case of failure allow to “roll-forward” to particular point in time. In other words if you have full database backup made at T0 and transaction logs from that point and something bad happens at T1 then you can always recover your database to any point in time between T0 and T1 by recovering from full backup and then roll-forwarding.
Large Objects or LOBs are objects like video, audio, scanned documents, etc. It’s a type which is available during table creation. One special thing about LOBs is that they are logically created as a column of table which is stored in particular tablespace but are physically located in separate so called large object tablespace.
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