MySQL concat() to create column names to be used in a query?

Question

I would like to concatenate column names in a way that the first part of the column name is a string and the second part is a number which is the result of another query.

Answer 1

If the number of columns is fixed, then a non-dynamic approach could be:

select 
  case mytable.mycolumn
    when 1 then column1  -- or: when 'a' then columna
    when 2 then column2
    when ...
    else ...
  end as my_semi_dynamic_column
from ...