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DB2 v.2, release 2 is relational SQL-based DBMS that is designed to exploit the potentional of large-scale mainframes. DB2 features cross- memory capabilities, expanded storage, multiple address spaces, and abroad range of high-level support subsystems such as storage and communications access methods. TSO, CICS, IMS DB/DC, and batch processing can access DB2. The system can store huge amounts of data including tables containing up to 64 gigabytes data. A sophisticated query optimizer improves performance. DB2 offers a number of methods for controlling access to data and programs including views, authority and ownership privileges, administrative authori- sation, password protection, and audit trace. DB2 offers a number of features that guard against subsystems, media, and application failures, and minimize the downtime of the system. It comes with over a dozen utility programs such as LOAD,REORG, RECOVER, REPAIR, etc. It provides three locking level to deal with problems of concurrent access. Version 2.2 provides access to distributed data accross multiple systems. DB2 conforms with SAA.ÊÎÌÏÀÍÈÈ ÎÁËÀÑÒÈ_ÏÐÈÌÅÍÅÍÈß