Question

I am essentially trying to accomplish this following:

Table 1:

MemberID   |    selection 1     |    selection 2     |     selection 3
-----------------------------------------------------------------------
12345      |        A           |                    |                 
12345      |                    |       B            |                   
12345      |                    |                    |          C

Transforms into

Table 2:

MemberID   |    selection 1     |    selection 2     |     selection 3
-----------------------------------------------------------------------
12345      |        A           |       B            |        C        

Part of me thinks a ‘UNION’ is the way to go but this is normally reserved for columns into rows I believe.

Any ideas?

Answer 1

My first thought is an aggregation trick. Are the columns without data NULL or just blank? Perhaps the values sort above or below the blank columns. In that case:

SELECT MAX(column1),MAX(column2),MAX(column3) FROM table GROUP BY MemberID;