Question

I have a database table like this:

id   |   check_number        |   amount
1    |   1001]1002]1003      |   200]300]100
2    |   2001]2002           |   500]1000
3    |   3002]3004]3005]3007 |   100]300]600]200

I want to separate the records into something like this:

id   |   check_number    |   amount
1    |   1001            |   200
2    |   1002            |   300
3    |   1003            |   100
.    |     .             |    .
.    |     .             |    .
.    |     .             |    .

How do I do this just using SQL in Oracle and SQL Server?

Thanks,

Milo

Answer 1

In Oracle Only, using the CONNECT BY LEVEL method (see here), with several caveats:

select rownum, id,
       substr(']'||check_number||']'
              ,instr(']'||check_number||']',']',1,level)+1
              ,instr(']'||check_number||']',']',1,level+1) 
               - instr(']'||check_number||']',']',1,level) - 1) C1VALUE,
       substr(']'||amount||']'
              ,instr(']'||amount||']',']',1,level)+1
              ,instr(']'||amount||']',']',1,level+1) 
               - instr(']'||amount||']',']',1,level) - 1) C2VALUE
    from table
connect by id = prior id and prior dbms_random.value is not null  
      and level <= length(check_number) - length(replace(check_number,']')) + 1


ROWNUM ID  C1VALUE C2VALUE

1      1   1001    200
2      1   1002    300
3      1   1003    100
4      2   2001    500
5      2   2002    1000
6      3   3002    100
7      3   3004    300
8      3   3005    600
9      3   3007    200

Essentially we blow out the query using the hierarchical functions of oracle and then only get the substrings for the data in each “column” of data inside the check_number and amount columns.

Major Caveat: The data to be transformed must have the same number of “data elements” in both columns, since we use the first column to “count” the number of items to be transformed.

I have tested this on 11gR2. YMMV depending on DMBS version as well. Note the need to use the “PRIOR” operator, which prevents oracle from going into an infinite connect by loop.