Dynamic data entry with stored procedure

I want to impliment a dynamic stored procedure that inserts data to a specific table, without knowing any specifics of the table

Ie if I have tableA and tableB

TableA (item1int, item2 varchar(10), item3 float)
TableB (abc int, def float char, ghi char(10), jkl float)

I want to have a procedure that is called

exec sp_insert('TableA'   ,  'item1, item2'  , '123, abc')   or
exec sp_insert('TableB'   ,  'abc, ghi, def'  ,  '32,gfd,x')

I have been able to split the list of items and data into a table variable

@inserts table( itm varchar(20), dta varchar(20) )

but my main problem is that I want to cursor through this, and build a dynamic statement that updates the table with each data point.


solution 1 fails as the data string is not surrounded by single quotes

declare @cmd nvarchar(4000)
cursor...
set @cmd=' update [' + @tbl + '] set [' + @itm + '] =  ' + @dta + ' where @headerid=1 '
exec sp_executesql @cmd
deallocate ...


solution 2 fails as I cannot reference a table or colum name with a variable

cursor ---
update @tbl set @itm = @dta where headerid=1
deallocate


Any ideas
Marts