CREATE OR REPLACE TRIGGER SYS.set_default_schema
after logon on <user_name>.schema
begin
execute immediate 'alter session set current_schema=<Schema_Name>';
end;
/
Example:
Here the user name is munna and schema name is scott
CREATE OR REPLACE TRIGGER SYS.set_default_schema
after logon on munna.schema
begin
execute immediate 'alter session set current_schema=SCOTT';
end;
/