PARTITION HASH (ITERATOR)

Description

Executes child operations for each partition in the table specified by the iterator

Versions

This operation was introduced in Oracle 8.1.5

This operation is implemented in the following versions

8.1.5
8.1.6
8.1.7
9.0.1
9.2.0
10.1.0
10.2.0

Example

This example was developed using Oracle 9.2.0.1 on Windows 2000

This example requires the following table and index definitions

    CREATE TABLE t1 (c1 NUMBER,c2 NUMBER)
    PARTITION BY HASH (c1)
    PARTITIONS 4;

    CREATE INDEX i1 ON t1 (c1) LOCAL;

The table does not need to be analysed

The statement

    SELECT c2 FROM t1
    WHERE c1 IN (10,20,30);

generates the following execution plan

0     SELECT STATEMENT Optimizer=CHOOSE
1   0   INLIST ITERATOR
2   1     PARTITION HASH (ITERATOR)
3   2       TABLE ACCESS (BY LOCAL INDEX ROWID) OF 'T1'
4   3         INDEX (RANGE SCAN) OF 'I1' (NON-UNIQUE)