WINDOW (NOSORT)

Description

Analytic function

Versions

This operation was introduced in Oracle 8.1.6

This operation is implemented in the following versions

8.1.6
8.1.7
9.0.1
9.2.0
10.1.0
10.2.0

Example

In this example the indexed column must be NOT NULL.

This example was developed using Oracle 9.2.0.1 on Windows 2000

This example requires the following table definition 

    CREATE TABLE t1 (c1 NUMBER NOT NULL,c2 NUMBER);

    CREATE INDEX i1 ON t1 (c1);

The table must be analysed 

    ANALYZE TABLE t1 COMPUTE STATISTICS;

The statement 

    SELECT c2, RANK () OVER
    (
      ORDER BY c1
    )
    FROM t1;

generates the following execution plan 

0     SELECT STATEMENT Optimizer=CHOOSE
1   0   WINDOW (NOSORT)
2   1     TABLE ACCESS (BY INDEX ROWID) OF 'T1'
3   2       INDEX (FULL SCAN) OF 'I1' (NON-UNIQUE)