unique value based on another column?

[jairathnem]

Hello,

 

My scenario is I need to have a unique value in a column based on value from another column.

 

for ex : I have item_ID and product column

 

For every item_ID there should only be unique values in the product column.

 

item_ID    Product

1               1

1               2

1               4

2               1

 

 

but if I insert 1 in item_ID and 1 in product now, it should throw an error.

I have no idea how to implement this. Any help appreciated.

[Barand]

Specify a unique key on (Item_id, product)

[jairathnem]

Thanks Barand. Unique index does the job