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Old 11-27-2006, 04:34 AM
sparrow sparrow is offline
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Default Join order..........

hi guys,
Would the ordered of the joins make a difference on large tables i.e.
SELECT T1.*, T2.*, T3.* FROM T1
LEFT JOIN T2 ON T1.id = T2.id
LEFT JOIN T3 ON T1.id = T3.id
WHERE ......

be any different from
SELECT T1.*, T2.*, T3.* FROM T1
LEFT JOIN T3 ON T1.id = T3.id
LEFT JOIN T2 ON T1.id = T2.id
WHERE ......

and would the following make a difference as welljoin order

SELECT T1.*, T2.*, T3.* FROM T1
LEFT JOIN T2 ON T1.id = T2.id
LEFT JOIN T3 ON T2.id = T3.id
WHERE .....

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  #1  
Old 11-27-2006, 04:34 AM
sparrow sparrow is offline
Junior Member
 
Join Date: Nov 2006
Posts: 1
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
sparrow is on a distinguished road
Default Join order..........

hi guys,
Would the ordered of the joins make a difference on large tables i.e.
SELECT T1.*, T2.*, T3.* FROM T1
LEFT JOIN T2 ON T1.id = T2.id
LEFT JOIN T3 ON T1.id = T3.id
WHERE ......

be any different from
SELECT T1.*, T2.*, T3.* FROM T1
LEFT JOIN T3 ON T1.id = T3.id
LEFT JOIN T2 ON T1.id = T2.id
WHERE ......

and would the following make a difference as welljoin order

SELECT T1.*, T2.*, T3.* FROM T1
LEFT JOIN T2 ON T1.id = T2.id
LEFT JOIN T3 ON T2.id = T3.id
WHERE .....

Thanks in advance -- This message may have been cut off and the rest will only be shown to members. To become a member, click here --
Reply With Quote