If your table has a self-growing column, you can use the following statement to do it once, and you can ensure that the code will not insert duplicate values.

Declare @ namevarchar (4);

-Max (id) is the maximum value of the self-growing column id.

set @ name =(right(' 0000 '+convert(varchar(5)，((select max(id)from table)+ 1)，4))；

-print @ name；

Insert into table value (@ name);

Select * from table