Question

I have table ItemPropertyValue with unique ID and PropertyID

ID IDProperty Value ItemID
1  1            1    5 
2  2            2    6
3  3            2    10
4  4            2    15

And another table called PropertyCategory

IDProperty  Value  Name
1           1      First Option
1           2      Second Option
2           1      Another option

What I want – it’s to select PropertyID from first table ItemPropertyValue where ItemID = 10 and then join with second table PropertyCategory

So I have smth like this:

IDProperty  Value  Name
1           1      First Option
1           2      Second Option
2           1      Another option

I tried this but there is an error. No such column as PropertyID

    SELECT * FROM PropertyCategory JOIN 
    (SELECT ItemPropertyValue.IDProperty AS PropertyID
    WHERE ItemPropertyValue.IDItem = '10') 
    ON PropertyCategory.IDProperty = PropertyID

How can I do it?

MS SQLServer if any

Answer 1

Use table alias:

SELECT * 
    FROM PropertyCategory 
    JOIN 
        (SELECT ItemPropertyValue.IDProperty AS PropertyID 
            WHERE ItemPropertyValue.IDItem = '10') as T
        ON PropertyCategory.IDProperty = T.PropertyID