AS400 SQL : Case When

Scenario:

Container  field in CONT file is build as Julian Day (3 Digit)+ 6 Digit sequence number. Julian Day (3 Char) is also field in CONT file. Below query will identify all the records that are having Jul_Day and first 3 digit are not matching using Case when condition.

select * from Cont

where                                                       

                                                      

int(Jul_Day) <> case                                          

               when length(trim(char(container))) = 8       

                then int(substr(char(container),1,2))       

               when length(trim(char(container))) = 7       

                then int(substr(char(container),1,1))       

               Else                                          

                    int(substr(char(container),1,3)) end