Question

SOURCE_TABLE 
------------
OID EVENT_ID  
1   1111  
2   2222
3   1111  
4   1111  
5   1111  
6   2222  
7   2222  
8   2222  

FINAL_TABLE  
------------
SNO EVENT_ID    OID LINE_NUMBER  
1   1111        1   1  
2   1111        1   2  
3   1111        3   3   
4   1111        3   4  
5   1111        4   5  
6   1111        4   6  
7   1111        5   7  
8   1111        5   8  
9   2222        2   1  
10  2222        2   2  
11  2222        6   3  
12  2222        6   4  
13  2222        7   5  
14  2222        7   6  
15  2222        8   7  
16  2222        8   8

I am using Oracle 11g. I want to insert data from SOURCE table to the FINAL table. In the FINAL table Line Number need be unique for each EVENT_ID (eg. 1111).

Answer 1

Suppose SNO is a auto increment PK in the Final_Table. Use ROW_NUMBER() function:

insert into FINAL_TABLE   (EVENT_ID,  OID,  LINE_NUMBER)
  (
    select EVENT_ID,OID,
       ROW_NUMBER() OVER(PARTITION BY EVENT_ID ORDER BY OID) as LINE_NUMBER
    from source_table
  );