Adam Zerner

I did have a sense that it wasn't The Rails Way, but I also had a sense that it was quite readable and sufficient. The code was working well locally, so I issued a pull request.

When I issued the PR, someone pointed out a major issue. SmsLog.all is going to fetch all of the sms logs in our database. Suppose there's 100 million of them. That'd be a very expensive query, taking all 100M rows from the DB and loading them into memory on the server. Instead, we could say to the database, "Hey, could you give us just the sms logs from John's campaign?". Suppose there's 30k of those. Now we only have to load 30k records into memory on our server instead of 100M. Much better.

I felt bad about this mistake. I've been programming for eight years. Of course you don't want to load 100M records into memory on your server. Duh. How could I get such a basic thing wrong?

A cognitive behavioral therapist would call this a dysfunctional thought. And they'd ask me to come up with a rational response to the thought. Well, here's my attempt at a rational response.

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