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create table "user"(
id VARCHAR(50),
name VARCHAR(50)
);
insert into "user"
values ('1', 'John Doe'),
('2', 'John Roe'),
('3', 'Jane Doe');
3 rows affected
select * from "user"
order by case id
when 1 then 1
when 2 then 2
end;
ORA-00932: expression is of data type NUMBER, which is incompatible with expected data type CHAR