mysql - unique value based on another column value? -


The issue is that I should have a unique value in the column based on price from the second column.

For pre: I have item_ID and product columns

Only item columns for each item_id should have unique value. 

  item_ID Product 1 1 2 1 4 2 1   
 But if I include 1 in item_ID and now 1 in the product, then it will be an error Should not throw it I do not know how to implement it. Any help appreciated.  
  
 
 
 You have a unique index for both columns  
  Change your unique index (item_id, product);

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