This blog is becoming more a collection of mistakes I’ve made than anything else, but I believe learning from other people’s mistakes is important. So each time I do something not-so-smart, I am sharing it here.
I was not sure how to call this post, and still not sure the name reflects the contents, so let me proceed to the story:). It has been over a year since I’ve started to rewrite the pieces of an old system, one by one. And granted in the very beginning I didn’t know the data so well, so after a year in production I could rewrite most of them much better.
But what is more important, that data itself has changed as well. One of the important changes was that a year ago we were using two external service providers for loans processing, and now for several months we are not using one of them (except of the servicing of the old loans). But it turned out, that I had a step in my code (which BTW had to be executed every two hours!) which would try to fill in the ID from this old system which we are not using anymore – for all records, which do not have this ID assigned! Which means, (since we do not use this system) that every two hours I was scanning all records – for nothing!
After I commented out this loop, the execution time for the whole process became pretty much invisible.
… now – how I should title this post?!