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Sql Classic join conditions order
Is the order of the where clause conditions important where you do an outer join (using *= or =*)?
I mean if you have 3 conditions in your where clause and some/all of them are *= or =*, is the order important? I tried a lot of examples and it seams not to count.
Is the order in which you write your left join, right join important? This make more sense to me to make a difference because the whole result is being joined with the new table.
If yes can i have an example, if no, why.
Please make some light into my life.
I mean if you have 3 conditions in your where clause and some/all of them are *= or =*, is the order important? I tried a lot of examples and it seams not to count.
Is the order in which you write your left join, right join important? This make more sense to me to make a difference because the whole result is being joined with the new table.
If yes can i have an example, if no, why.
Please make some light into my life.
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lets say you have 3 tables a, b, c and the select:
select * from
a left join (b left join c 0n b.f1 = c.f1) on a.f1 = c.f1
Fist i thought that is the same as
(b left join c on b.f1 = c.f1)
right join a on a.f1 = c.f1
Can you re-write the first statement just using where clauses?