Performs a cartesian join between two tables
This operation is implemented in the following versions
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Note that at least one of the tables must be analyzed otherwise a NESTED LOOPS execution plan is executed.
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); CREATE TABLE t2 (c1 NUMBER);
The table does not need to be analysed
The statement
SELECT t1.c1,t2.c1 FROM t1,t2;
In Oracle 9.2 generates the following execution plan
0 SELECT STATEMENT Optimizer=CHOOSE 1 0 MERGE JOIN (CARTESIAN) 2 1 TABLE ACCESS (FULL) OF 'T1' 3 1 SORT (JOIN) 4 3 TABLE ACCESS (FULL) OF 'T2'
In Oracle 10.2 generates the following execution plan
0 SELECT STATEMENT Optimizer=CHOOSE 1 0 MERGE JOIN (CARTESIAN) 2 1 TABLE ACCESS (FULL) OF 'T1' 3 1 BUFFER (SORT) 4 3 TABLE ACCESS (FULL) OF 'T2'