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The names describe their uses. This is especially useful for the fact-fact join (query 82 in the TPC DS benchmark).

SMB Join across tables with different keys

If the tables have differing number of keys for example Table A has two SORT columns and Table B has 1 SORT column, then you might get an index out of bounds exception.

The following query results in an index out of bounds exception because emp_person let us say for example has one sort column while emp_pay_history has 2 sort columns.

SELECT p.*, py.*
FROM emp_person p INNER JOIN emp_pay_history py
ON   p.empid = py.empid

This works fine.

SELECT p.*, py.*
FROM emp_pay_history py INNER JOIN emp_person p
ON   p.empid = py.empid
WHERE p.etl_process_run_id

Generate Hash Tables on the Task Side

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