Deciphering ramifications from a log message alone is a pretty unusual way to approach a problem. You still have your 1990s Nagios-style application monitoring, right? So when you wake up to a message that the web monitor says it's not possible to add items to the shopping basket right now, the database monitor signals an unusually long response time, the application metrics tells you number of buys is at a fraction of what is normal for this time of day, then that WARN log message from the application telling you about a foreign index constraint is violated is pretty informative!