Conversion of Oracle DECODE to MySQL CASE

The Oracle DECODE function is used to compare the specified expression to each search value one by one and return the corresponding result.

MySQL also supports the DECODE function, but it is used to decode the encrypted strings using the specified password. The MySQL CASE expression is an equivalent of the Oracle DECODE function.

SQLWays converts the Oracle DECODE function to the MySQL CASE expression.

Example:

TABLE 23. Conversion of Oracle DECODE to MySQL CASE

Oracle	MySQL
create procedure ora_sp_decode2 (job_level out varchar2) as begin select DECODE(job_lvl,1,'level 1',2,'level 2','Unknown level') into job_level from employee where job_id>0; end;	create procedure ora_sp_decode2 (out job_level TEXT ) begin select CASE job_lvl WHEN 1 THEN 'level 1 WHEN 2 THEN 'level 2' ELSE 'Unknown level' end into job_level from employee where job_id>0 ; end ;