I have to build a table  that holds warehouse information

It should be letter of cell (a,b,c,d,....) and  number of cell
(1,2,3....300) , isempty  (bit default =0)

How would you create a table to hold such info like give all empty cells
under letter cell 'a'?

If I want to flll cell 'A'1=0  how would update the table?

Thanks

create table excel_sheet (
   row_id varchar(1) not null,
   col_num int not null,
   value numeric(19) null,
   primary key pk_sheet (
     row_id,
     col_num
   )
)

create index...

        robert