This post is a great extension of Kevin Frank’s first post on anti-deduping–keeping duplicates and omitting unique entries from within an existing found set. Now, keeping duplicates is an unusual request, but the techniques Frank develops in these two posts are useful to hone your coding skills and improve your approach to solving a problem:
In part one, we explored various “anti-deduping” techniques. As you may recall, the challenge was to retain duplicates and omit unique entries from within an existing found set, as opposed to starting from all records… otherwise we could have just searched on ! (find all duplicates), but the ! operator does not play nicely with constrain, and cannot help us with this particular challenge.
Also, last time, we were seeking to omit unique zip (postal) codes, which, in the example file, were always five digits long, i.e., of fixed length. Today our goal is to omit unique (a.k.a. “orphaned”) first names, and it turns out there are some additional challenges when the field in question is of variable length, which we will explore in today’s demo file: Anti-deduping, part 2.
In this post, Frank explores three different ways to isolate records using three different functions:
Check it out and pay attention to how Frank uses the new FileMaker 13 Summary List function to build a list to compare values in an active field. Also note the speed tests results for large sets both locally and for test run across a WAN.
FM 13: Anti-deduping, part 2 | FileMakerHacks.