Thursday, June 11, 2009

Logical Query Processing Phases - Order of Statement Execution

1. FROM
2. ON --Interesting Observation of ON Clause on LEFT JOIN –
How ON Clause Effects Resultset in LEFT JOIN.

3. OUTER
4. WHERE
5. GROUP BY
6. CUBE | ROLLUP
7. HAVING
8. SELECT
9. DISTINCT
10 ORDER BY
11. TOP

I have given the Execution plan for Inner join. i.e.
If we give our condition in the ON CLAUSE or in the
WHERE CLAUSE it gives the same execution plan.






But for left join the execution plan differs and
the ResulSet also differ.





For clear details read Journey to SQL Authority's the two links.


Logical Query Processing Phases – Order of Statement Execution


Interesting Observation of ON Clause on LEFT JOIN – How ON Clause Effects Resultset in LEFT JOIN

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