POSTGRES IF statement fails

Question

I'm new to conditional statements within postgres. I have the following statement SELECT IF status = 'L' THEN edate ELSEIF status = 'C' THEN 'wrong date' END IF as date FROM campaigns;

But I get an error

ERROR:  syntax error at or near "status" at character 11
LINE 1: SELECT IF status = 'L' THEN edate ELSEIF status = 'C' THEN '...

May I use it like this or what am I doing wrong?

Answer 1

IF isn't part of SQL syntax, can't work. Use a CASE:

SELECT 
  CASE status
    WHEN 'L' THEN edate 
    WHEN 'C' THEN 'wrong date' 
  END as date 
FROM 
  campaigns;

Ps. If "edate" is of type DATE or TIMESTAMP, you have to cast this column to a VARCHAR because 'wrong date' is not a DATE nor TIMESTAMP.