Question

Imagine the below table as A

col1 col2 col3 rank
 1     2   n    5
 1     2   n    6
 2     3   a    3

While inserting below records from table B to table A, the rank column valus should be keep incrementing if the same records inserts.

Records in table B which gonna insert into A are

col1 col2 col3
 1     2    n
 2     3    a

The desired output in table A after the above records are inserted is,

 col1 col2 col3 rank
   1    2   n    5
   1    2   n    6
   1    2   n    7
   2    3   a    3
   2    3   a    4

Please help me how to acheive this.Thanks.

Answer 1

If the record in B are unique, then you could use a query like this

————–EDIT——————-

If B can have multiple records, you can use row_number() funcion with partition

insert into TestA
select b.*, 
(select max([rank]) from TestA where col1 = b.col1 and col2 = b.col2 and col3 = b.col3) 
+ row_number()over (partition by col1, col2, col3 order by col1, col2,col3 asc) as N
 from TestB b

————–END EDIT——————-

Note: i renamed the table: TestA and TestB

insert into TestA
select b.*, (select max([rank])+1 from TestAwhere col1 = b.col1 and col2 = b.col2 and col3 = b.col3)
 from TestB b

or with a JOIN like this

insert into testa
select b.*, mr+1 from TestB b
join
(select col1, col2, col3, max([rank]) as mr
from TestA A
group by col1, col2, col3) as M
on 
b.col1 = M.col1 and b.col2 = M.col2 and b.col3 =M.col3