CONNECT By Prior...or something else...

Question

I have a very simple audit table with the following format:
Input_File Varchar2(256)
Output_File Varchar2(256)
Date
The table basically keeps tracks of files going through my systems. At a later point in processing, what was an Output_File for record 1, can be the Input_File of record two. If a single Input_File generates several output files, then a second branch would be generated based upon that output file name. Here are a few example records - I have only shown an example of only 1 branch:
Row Input_File Output_File
1 RWMS.00024928.DAT RWMS.00024928.DAT
2 RWMS.00024928.DAT 943RWMS.00024928.DAT
3 943RWMS.00024928.DAT CA943RWMS.00024928.DAT.presort
4 CA943RWMS.00024928.DAT.presort CA943RWMS.00024928.DAT
(I have intentionally left Date out of this example.)
What I am trying to do is find the first Input_File with an associating Output_File. When I need this information, it will be based upon the final output filename; which in this case is the file CA943RWMS.00024928.DAT. So, in this case the orignal input filename is RWMS.00024928.DAT.
Currently, I am using the option 'CONNECT BY Prior' to link Input_File of row 4 to Output_File of Row 3 and so on. This works OK when there are not too many records in the table. However, when the table gets pretty big, the query takes longer and longer to run.
Is there a more efficient method than using 'CONNECT BY Prior'? If so, how would I go about writing the SQL to do that?
Regards,
Richard.

Answer 1

Faheem1 wrote:
FATHER, CHILD_NUM, CODE, CODE_QTY
a 1 b 1
b 1 c 1.5
c 1 d 2
d 1 e 1
There are 3 columns father,child_num,code & the code_quantity.
It is explained as 'a' is my FINAL finished good and is produced from raw material 'b' using 1kg.
and here 'b' becomes my finished good and is produced from raw material 'c' using 1kg.
and here 'c' becomes my finished good and is produced from raw material 'd' using 1kg.
and here 'd' becomes my finished good and is produced from raw material 'e' using 1kg.how much of 'a' is produced from raw material 'b' using it 1 kg? is it 1 kg itself....??
And also what values 1,1.5,2.1 specify in above table...
If everything is 1:1 is product:rawmaterial ratio then 20kg of 'a' requires 20 kg of 'e'
Ravi Kumar
Edited by: ravikumar.sv on Nov 6, 2009 1:38 PM