If you have DB2, I would load that into a DB2 table and use JOIN processing.
Or if you have SAS, I would use PROC SQL. Lizette > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On > Behalf > Of David Speake > Sent: Thursday, October 04, 2012 4:48 PM > To: [email protected] > Subject: Design of Key Matching application > > One of my application programmers asked for information on design decision. > > Given two files that are not in order by the match key. > Assuming the smaller file has at most one record per possible key value. > Larger file may have multiple records for some keys and may also have values > not > found in the smaller file. > Assume optimal blocking, buffering, both files, both solutions. > Which is more efficient? > > Sort the smaller by that key, load to VSAM, then pass the unordered larger > file and do > random retrievals from the VSAM file. > > Sort both PS files by key in question and pass sorted files for matching by > key. > > We both (sorta) think the answer is ... "It depends" but on what criteria? > > Number of records in each file? Which is more important? And by how much? > Record lengths? Same as above? > Length of key field in question? (Within SORT and VSAM length restrictions of > course). > Key bias in larger file? > Ratio of hits/non hits? > > Anyone have a nice formula? :-) > > David Speake ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
