Question

I have table with 3 columns. One is Id, second column is Name and the third one Description. How can I select the value in the Description field by giving the column index, 3?

Thanks in advance

Answer 1

You can’t, from plain SQL (other than in the ORDER BY clause, which won’t give you the value but will allow you to sort the result set by it).

If you are using another programming language to construct a dynamic query, you could use that to identify the column being selected by its index number.

Alternatively, you could parameterise your query to return a specific column based on a case statement – like so:

select a, b, c, d, e, ...,
       case ?
           when 1 then a
           when 2 then b
           when 3 then c
           when 4 then d
           when 5 then e
           ...
       end as parameterised_column
from ...