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Editorial Team
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Asked: 2026-06-11T09:16:27+00:00

Lookup table – unique row identity The other lookup tables just do not make

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Lookup table – unique row identity

The other lookup tables just do not make sense as from what I have seen giving a row an ID then putting that id in another table which also has a id then adding these id’s to some more tables which may reference them and still creating a lookup tables with more id’s (this is how all the examples I can find seem) What I have done is this : 

product_item - table
------------------------------------------
id | title   | supplier   | price 
1  | title11 | suuplier1  | price1

etc.
it then goes on to include more items (sure you get it)

product_feature - table
--------------------------
id | title    | iskeyfeature 
1  | feature1 | true




feature_desc - table
-----------------------------
id | title | desc
1  | desc1 | text description





 product_lookup - table
    item_id | feature_id | feature_desc
    1       | 1          | 1
    1       | 2          | 2
    1       | 3          | 3
    1       |64          | 15

(as these only need to be referenced in the lookup the id’s can be multiples per item or multiple items per feature)

What I want to do without adding item_id to every feature row or description row is retrieve only the columns from the multiple tables where their id is referenced in the same row of the lookup table. I want to know if it is possible to select all the referenced columns from the lookup row if I only know the item_id eg. Item_id = 1 return all rows where item_id = 1 with the columns referenced in the same row. Every item can have multiple features and also every feature could be attached to multiple items , this will not matter if I can just get the pattern right in how to construct this query from a single known value.

Any assistance or just some direction will be greatly appreciated. I’m using phpmyadmin, and sure this will be easier with some php voodoo I am learning mysql from tutorials ect and would like to know how to do it with sql directly.

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1 Answer

  1. Editorial Team

    Having a NULL value in a column is not the major concern that would lead to this design – it’s the problem with adding new attribute columns in the future, at which MySQL is disgracefully bad.

    If you want to make a query that returns everything about an item in one row, you need to LEFT OUTER JOIN back to the product_lookup table for each feature_id. This is about every 10th mysql question on Stack Overflow, so you should be able to find tons of examples.

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