Category: Architecture


Understanding ROWID In Oracle Database

Every record has a unique ROWID (pseudocolumn) within a database representing the physical location on disk where the record lives….


Understanding Index Compression In Oracle Database 19c

From Oracle 9i onward both non-unique and unique indexes can be compressed to save disk space. The COMPRESS [N] clause…


Understanding DELETE vs TRUNCATE In Oracle Database

In Oracle, Segment Space Management is managing the space within a segment. In a segment generally you have USED block…


Understanding DBMS_SHARED_POOL Package

The DBMS_SHARED_POOL package provides access to the shared pool, which is the shared memory area where cursors and PL/SQL objects…


Row Migration Vs Row Chaining

Oracle database allocates logical space for all data in the database. Logical storage structures are recognized by Oracle DB and…


Understanding LOCKING In Database

CONCURRENT access is accessing same data by multiple users at the same time. • SHARED lock is acquired when user…


Understanding TRANSACTIONS In Database

What Is A Transaction ? Transaction is logically joining multiple SQL statements (unit of work) which we can either commit/rollback.In…


Understanding FLASHBACK Technology

In Oracle database,under SGA there is an optional memory component known as – Flashback buffer.When Flashback Database is enabled, the…