When I came into the ACE world serveral years ago, there wasn't much of a part database so I was forced to buld my own. This was done mostly on an "as needed" basis, so I didn't spend a lot of up front time with it. The nice thing is that I have a database that is in the format that I am used to looking at. It may not have all of the data for each part, but it gets the materials purchased with some idea of what a part is.
I don't know who made the entries for the recent catalogs, but from what I have seen, I prefer to keep my custom database. And no offense is intended to anyone here. I've looked at the latest catalog, and in my humble opinion there is just way too much information in the descriptions, etc. And there doesn't seem to be much of a logical pattern to it. It looks like non-electrical people have read MFG's catalogs and made the entries from that, without having a clue about what he parts are. OK, so I am a bit judgemental. I beg forgiveness!
Most of the part numbers that I would use don't match the company stardards, but we are a bit different than the rest of the industry. We don't order a complete pushbutton. We assemble the operator, contact block, etc. from a stock of parts, so that's the way the BOM is listed.
Of course, the out of the box database has to contain the parts for many MFGs so that it is useful for everyone. Unfortunately, as mentioned in other posts in this thread, some companies are not too willing to part with their information. So much for the common good of the industry. It's all about contracts and money. Did I mention that it's all about money?