oracle-11g Tutorials, Tips & Tricks

Oracle Skip Locked

Oracle Skip Locked

Oracle 11g introduced SKIP LOCKED clause to query the records from the table which are not locked in any other active session of the database. This looks quite similar to exclusive mode of locking. The select for...

Index Skip Scan in Oracle

Index Skip Scan in Oracle

With Oracle 9i, the Cost-Based Optimizer (CBO) is equipped with many useful features, one of them is “Index skip scan“. In previous releases a composite index could only be used if the first column,...

Oracle 11G new feature: Virtual Column

Oracle 11g introduced the concept of ‘Virtual Column’ within a table. Virtual Columns are similar to normal table’s columns but with the following differences: They are defined by an expression. The result of evaluation...