Comment by hdjrudni

This one company I worked for created like 5 databases for every client they had.

So we had hundreds of databases. And no migrations or way to keep them in sync.

One day I got fed up and ran some statistical analysis on all the databases to find inconsistencies and figure out what the most popular schemas were, because sometimes even when they had the same table and column names, the types were slightly different.

I don't recall if I managed to get them all in sync before I quit.