How to call a function in SQL

 (SELECT [dbo].[fn_LookupValueById](93949))

select convert(parameters)

table value function will be called as which return type is table and scaler value functions are int, string is return type.

SELECT * from hrms_pay.dbo.fn_GetAllChildOffices (9)

Note :- Please donot use [ ]"square brackets " with function name.

Also sometime we use dbo.function name. (dbo with function name)