Group rows together based on column values. Number of rows returned is restricted using the ROWNUM pseudo-column.
This operation is implemented in the following versions
This example was developed using Oracle 220.127.116.11 on Windows 2000
This example requires the following table definition
CREATE TABLE t1 (c1 NUMBER);
The table does not need to be analysed
SELECT * FROM ( SELECT c1 FROM t1 GROUP BY c1 ) WHERE ROWNUM < 10;
generates the following execution plan
0 SELECT STATEMENT Optimizer=CHOOSE 1 0 COUNT (STOPKEY) 2 1 VIEW 3 2 SORT (GROUP BY STOPKEY) 4 3 TABLE ACCESS (FULL) OF 'T1'