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Comment by Mutjake | Hacker News Reader

I sort of feel the same…but on the other hand if you consider ”delete from” exists also, it’s not completely unsensible to consider you first tell what operation you’re about to perform to the data. Would be nice to start with the source entity name for sure. Dunno what ”select 1” would look like, I guess the from foo would be optional.

Random saturday ramblings, sorry about that :-D

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DELETE FROM is even worse. Accidentally/mindlessly press cmd+enter before you wrote the WHERE? Poof, data gone. Make it FROM … DELETE!

I also wish we needed to explicitly take locks. In PostgreSQL at least (I think other dialects/engines too), figuring out what operation will take what lock and potentially mean downtime is left as an exercise to the reader. Force me to write WITH EXCLUSIVE TABLE LOCK when I add a non nullable column with a default!

If you're going to run commands that modify data directly on the cli, do it in a transaction so you can roll back. Also, start with `--` to make it a comment. Once you have the correct query and someone's checked your work, go back to the beginning of the line and remove the `--` so you can run it. It's also a good idea to write a select * or count first to check that things make sense, and then start your transaction, go up and modify your select into a delete/update, check affected rows looks good again, maybe do another select or two to check that data looks like you expect, commit.

Fun fact: if you still have a MySQL (MyISAM) database, the transaction commands return success but don't actually function, so you can't roll back.

Well, to be fair ”from foo delete” would do the same I suppose :-D Unless there’d be an explicit end to the statement to designate you really want to delete everything. Which might not be a bad idea. Or make ”where …” mandatory and bring in ”delete_all” or ”delete everything from foo” as a syntactic guardrail. This is equally implementable, whichever the order of ”delete” and ”from” would be.

The MySQL client has an --i-am-a-dummy flag that won't let you run a DELETE (or UPDATE, I think) without a WHERE.

the Google SQL variant has where required for deletes. on my first encounter of it I was just like "huh, neat", you can always use 1=1 as the predicate if needed.

If you don't SELECT first before running the DELETE query, you shouldn't be anywhere near an IT job, let alone a production database.

Good tools prevent mistakes from happening rather than blaming the user for using it wrong

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