I want to get a new columns on table and this new columns need to contain another columns name separate by - example: (field_1-field_2) where the values = X

I can not hard code the column names because each time these column name are different depending on the projects.

|  id  |  field_1 | field_2  | field_3 |  field_4 |  field_5  | new_column              |
|  1   |     X    |  NULL    |      X  |  NULL    |     X     | field_1-field_3-field_5 |
|  2   |  NULL    |     X    |      X  |  NULL    |  NULL     | field_2-field_3         |
|  3   |  NULL    |  NULL    |   NULL  |     X    |  NULL     | field_4                 |