How would I select the column that contains the highest value for each row?
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ID Store Shoes Shirts Pants 01 A 1 2 3 02 B 3 1 2 03 C 2 3 1
I want to return something like:
A Pants B Shoes C Shirts
To get exactly what you asked for:
select Store , case when Shoes >= Shirts and Shoes >= Pants then 'Shoes' when Shirts >= Shoes and Shirts >= Pants then 'Shirts' when Pants >= Shoes and Pants >= Shirts then 'Pants' else null end from Stores
Ugly, and even uglier if you ever have to handle additional columns. Feel free to imagine what the query would look like if there were a realistic number of columns, like 187.
What you should do is have two tables instead of one:
Stores ID Store 01 A 02 B 03 C Inventory ID Item Qty 01 'Shoes' 1 01 'Shirts' 2 01 'Pants' 3 02 'Shoes' 3 02 'Shirts' 1 02 'Pants' 2 03 'Shoes' 2 03 'Shirts' 3 03 'Pants' 1
Now you can handle as many items as you wish with this query:
select Store , Item from Stores S inner join Inventory I on S.ID = I.ID where Qty = ( select max(Qty) from Inventory where ID = I.ID )
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