Question

I have a table that has three columns: myColumn, myColumn2 and myColumn3. The three columns can have a different value but they are all the same type.

I need to do a join such that I merge all the items in the three columns and then group by

If I had a single column, it would be done like this:

select distinct (myColumn), COUNT(myColumn) as 'TotalF' 
from FormularioCorto 
where idEvento = @idEvento and myColumn <> ''
group by myColumn 

The question is:
How do I do a TSQL statement that will allow for me to join the three columns and then group by?

Edit: here is the sample data
I have a table that has 3 columns with the same type

columna columnb columnc
a              a       b
b              a       b
c              c       d

I need to run a tsql that will merge the 3 columns and group by, to get a result like

newcolumn   count
a             3
b             3
c             2
d             1

Any ideas?

Thanks in advance

Answer 1

I think you mean concatenate rather than JOIN. JOIN has a very specific meaning with SQL. Use the + operator to concatenate string fields.