SQL Joins condtion and Where Condition

Question

I have a problem with the where condtions and inner join conditions.

They are:

ex:

select * from table1 T

inner join table2 F on F.tkey=T.tkey and F.date >= '20140104'

and

select * from table1 T

inner join table2 F on F.tkey=T.tkey

where F.date >= '20140104'

**here which will be execute faster and why ?

What exactly is the problem? Do these compile or not? Or are you simply asking which one will execute faster? — SEB BINFIELD, Aug 13 '14 at 14:06

score 1 · Answer 1 · answered Aug 13 '14 at 14:09

1

The sequence of execution of any SQL query is :

FROM ->ON ->JOIN -> WHERE -> GROUP BY ->WITH CUBE or WITH ROLLUP->HAVING->SELECT->DISTINCT->ORDER BY ->TOP

so first one will execute faster because it will filter rows on the basis of given criteria while joining itself, where as the second query will join the tables first and then go for filtering rows

answered Aug 13 '14 at 14:09

ankit

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That's not necessarily true - depending on what SQL Parser he is using and how the parser analyzes the statement he could have different results. In many cases, his query above is simple enough that it might pick the same execution plan for both queries. – Aug 13 '14 at 16:29

SQL Joins condtion and Where Condition

1 Answers1