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MySQL Left Join - Appending to variable

Posted on 2011-10-06
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Last Modified: 2012-05-12
I'm joining two tables.  

Let's say table one is...

Table Name: items

Item        ID
Widget    5

Table two:

Table Name: prices

Item Price         URLID
25.00               item/5

My SQL goes like...

SELECT *
FROM items t1
LEFT JOIN prices t2 ON t2.URLID = 'item'.t1.ID
WHERE t1.ID = '5'

What would the proper syntax be to do that?

As you can see - ID's variable in the first table (in this instance 5) relates to the 'item/VARIABLE' in the second table (in this instance, item/5).

The " t2.URLID = 'item'.t1.ID" is apparently wrong syntax - as it doesn't work.

How would I properly phrase that?

Thanks!
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Question by:erzoolander
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4 Comments
 
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Author Comment

by:erzoolander
ID: 36927917
'item/'.t1.ID I mean.  Forgot the slash
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Expert Comment

by:johanntagle
ID: 36927967
should just be t1.id. You don't need 'item' since you already aliased it with t1
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LVL 2

Author Comment

by:erzoolander
ID: 36928484
Will it match up though, since URLID = item/5 and t1.id = 5?

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Accepted Solution

by:
johanntagle earned 2000 total points
ID: 36928511
Ah missed that part.  So it should be t1.id/5.

It might cause a slow query though as it might not use an index in t1.id (if any).  Well, if it's just a one-time thing then that's okay.  If you plan to do this regularly, suggest you add another column to items with the values already divided by 5.
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