Parallel execution - broadcast rows to parent process
This operation is implemented in the following versions
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This example was developed using Oracle 10.2.0.1 on Linux
This example requires the following table definitions
CREATE TABLE t1 ( c1 NUMBER, c2 NUMBER ) PARALLEL 2; CREATE TABLE t2 ( c1 NUMBER, c2 NUMBER ) PARALLEL 2;
The statement
SELECT t1.c2,t2.c2 FROM t1,t2 WHERE t1.c1 = t2.c1;
generates the following execution plan
0 SELECT STATEMENT Optimizer=CHOOSE 1 0 SORT (AGGREGATE) 2 1 PX COORDINATOR 3 2 PX SEND (QC (RANDOM)) 4 3 HASH JOIN 5 4 PX BLOCK ITERATOR 6 5 TABLE ACCESS (FULL) OF 'T1' 7 4 BUFFER (SORT) 8 7 PX RECEIVE 9 8 PX SEND (BROADCAST) 10 9 PX BLOCK ITERATOR 11 10 TABLE ACCESS (FULL) OF 'T2'