Why we are using to_number function in this query?

[kishore Roul]

query like
select * from emp where deptno=To_numbe r(10)
i think it is used for tune the query ..yes on no.
plz give me the relevant answer

[amitpatel66]

Check if the datatype of the column deptno is Varchar in the table? Also using TO_NUMBER is to convert the value to number externally.