sql - Separation of JOIN and WHERE clauses -

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i have written same join 2 different ways:

select     one.first,     two.second,     three.third     onetable 1      inner join twotable 2         on one.twokey = two.onekey      inner join threetable 3         on two.twokey = three.twokey         , one.onekey = three.onekey  1=1     , one.firstnamefield in ('first name', 'second name', 'third name')     , two.secondnamefield not in ('last name', 'sirname', 'family name')     , three.thirdnamefield = ('nick name', 'pen name', 'handle')

and

select     one.first,     two.second,     three.third     onetable 1      inner join twotable 2         on one.twokey = two.onekey         , one.firstnamefield in ('first name', 'second name', 'third name')         , two.secondnamefield not in ('last name', 'sirname', 'family name')      inner join threetable 3         on two.twokey = three.twokey         , one.onekey = three.onekey         , three.thirdnamefield = ('nick name', 'pen name', 'handle')

as see, where portion first goes join in re-written query.

is there difference between two?

is 1 more desirable other?

there no difference in results since using inner joins. however, results quite different if these left joins.

i tend put conditions related join in join clause , conditions related overall filtering (a thin distinction i'll grant you) in clause. so, inclination have been first form.


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