decode is the PL/SQL function which allows us quickly to covert/update the column in the defined conditions.
decode ( COLUMN_NAME,
'OLD VALUE1','NEW VALUE1',
'OLD VALUE2','NEW VALUE2', ....
'OTHER VALUE' )
Here is the example:
Lets create the test table from dba_objects.
create table po.newtable as select * from dba_objects;
select distinct owner from po.newtable;
This sql statement is simply convert HR to NEW_HR, DEMO to NEW_DEMO, PUBLIC to NEW_PUBLIC and for the rest of the value covert to OTHERS.
update po.newtable set OWNER= DECODE(
It is very efficient to complete the update.