To go slightly OT, I have the current displeasure of becomming
acquainted with Sybase which has ideas about being flexible with
standards (and sanity) much like MySQL.
The first of the two intentional "helpful" features I have come across
so far is that inserting (or updating) char/varchar columns with
strings that are too long silently results in a truncated string.
The second is that in where clauses, NULL = NULL is true. (waits for
you to get up off the floor) Apparently it didn't use to be like that,
but the "feature" was added due to customer requests... What's worse
is that Sybase is not even internally consistent - FALSE = FALSE in
the join clause does not cause a match.
Truly horrible. Of course there are runtime parameters you can set to
get more ansi-ish behaviour, but by the time you realise this, there
may already production code that relies on the behaviour...