SQL using CASE with STRING function - sql

Question

I'm trying to write a SQL query that uses CASE and STRING together and getting an error.
This is what I'm trying to work on. Any help is greatly appreciated.
I tried adding in STRING function as well but also does not work.
SELECT Case
when sn.1_code = 1 then 'Attended -- ' ,
sn.mult_1 ,
, 'and' ,
sn.dict_2 ,
' also acted with ' ,
sn.dict_3 ,
'.' ,
when sn.1_code = 3 then 'left because ' ,
sn.mult_2 ,
'.' ,
when sn.dict_1 = 2 then 'Went home' ,
when sn.dict_1 = 24 then 'Canceled' AS 'Attendance'
FROM db.sn

Answer 1

It looks like you're trying to concatenate strings. The actual operator may vary depending on your server software, but the idea would be:
SELECT
Case
when sn.1_code = 1
then 'Attended -- ' + sn.mult_1 + 'and' + sn.dict_2 + ' also acted with ' + sn.dict_3 + '.'
when sn.1_code = 3
then 'left because ' + sn.mult_2 + '.' ,
when sn.dict_1 = 2
then 'Went home' ,
when sn.dict_1 = 24
then 'Canceled'
End AS 'Attendance'
FROM db.sn

Answer 2

As other answers have pointed out, you need to concatenate your string values together. From the very very very little I know of Intersystems Cache SQL (I just looked it up), you will need to use || to concatenate the values (you can also use the CONCAT() function to do this, but it only allows two paramaters):
SELECT Case
when sn.1_code = 1 then 'Attended -- ' ||
sn.mult_1 ||
'and' ||
sn.dict_2 ||
' also acted with ' ||
sn.dict_3 ||
'.'
when sn.1_code = 3 then 'left because ' ||
sn.mult_2 ||
'.'
when sn.dict_1 = 2 then 'Went home'
when sn.dict_1 = 24 then 'Canceled' END AS 'Attendance'
FROM db.sn
You also had some extra commas in there, as well as a missing END at the end of your CASE statement

Answer 3

Intersystems Cache appears to support the two argument concat() function (ala Oracle). It also supports string(). This should do what you want:
SELECT (Case when sn.1_code = 1
then string('Attended -- ', sn.mult_1, 'and', sn.dict_2 , ' also acted with ', sn.dict_3 , '.' )
when sn.1_code = 3
then string('left because ', sn.mult_2 , '.' )
when sn.dict_1 = 2
then 'Went home'
when sn.dict_1 = 24
then 'Canceled'
end) AS 'Attendance'
FROM db.sn;
The case statement also needs an end.

Answer 4

If you're trying to concatenate, as it seems to me, you do it with the + character, and not the comma:
SELECT
Case when sn.1_code = 1 then 'Attended -- ' +
sn.mult_1 +
'and' +
sn.dict_2 +
' also acted with ' +
sn.dict_3 +
'.'
when sn.1_code = 3
then 'left because ' + sn.mult_2 + '.'
when sn.dict_1 = 2 then 'Went home'
when sn.dict_1 = 24 then 'Canceled'
END AS 'Attendance'
FROM db.sn
Without seeing your example with the String function, I don't know what you were trying to do with it.