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Oracle Internals

FIRST ROW

Return the first row from a result set

This operation is implemented in the following versions

This example applies to Oracle 8.1.5 and above

This example was developed using Oracle 9.2.0.1 on Windows 2000

This example requires the following table definitions

    CREATE TABLE t1 (c1 NUMBER,c2 NUMBER);

    CREATE INDEX i1 ON t1 (c1);

The table does not need to be analysed

The statement

    SELECT /*+ INDEX (t1 i1) */ MIN (c1)
    FROM t1
    WHERE c1 > 0;

generates the following execution plan

0     SELECT STATEMENT Optimizer=CHOOSE
1   0   SORT (AGGREGATE)
2   1     FIRST ROW
3   2       INDEX (RANGE SCAN (MIN/MAX)) OF 'I1' (NON-UNIQUE)