I\'m looking for a string function that works like Oracle\'s DECODE Having table tab with a single column col
tab
col
col ---- a b c d
It may be easier to read and to inspect if you avoid nesting by using a flat CASE WHEN THEN expression :
SELECT CASE WHEN col = 'a' THEN 1 WHEN col = 'b' THEN 2 ELSE 9 END dec FROM tab