Why isn't "like" appropriate?

Because you can't just make stuff up? "LIKE" is a specific operator for matching strings where "%" can be used in one as a wildcard. It isn't some generic "roughly similar to" DWIM magical operator. Perhaps you should check your documentation?

Now, I often regret when I have to learn more about Oracle (because it usually means I've had to try to use Oracle) and I know Oracle does some rather bizarre things. But I'd still be rather surprised to find out Oracle took the string-comparing LIKE and overloaded it for testing if datetimes were "near".

As I indicated in my OP the query works in SQL Developer. Maybe it's massaging the code, or maybe newer clients support using "like" in that context. I actually did verify the code in SQL Developer, implying the problem could be a difference in the clients or with DBIx::Simple! You were on the right track (see the updated OP), but there was no need to be so hostile about it!

Elda Taluta; Sarks Sark; Ark Arks

As I indicated in my OP the query works in SQL Developer.

Yeah, it is common for DBs to allow you to silently treat a date or datetime as a string, so you often won't get any warning or error for saying "sometime LIKE somedate". But doing that just converts 'somedate' to a string, treats any resulting '%' characters (surely none) as wildcards, and then compares that to the stringification of 'sometime'. Is that what you wanted to do? If so, that is certainly a confusing way to accomplish it.

but there was no need to be so hostile about it!

I don't see where I could even be reasonably interpreted as "hostile" much less "so hostile". The closest I came to "hostile" was toward Oracle. Did you take that personally? Perhaps I should have been more like Dominus and instead said "You can't just make shit up, Retardo." At least that would've been rude. "Hostile" surely goes beyond "rude". I tried to find some examples of "hostile remarks" but every hit I checked just showed people being unwilling to even repeat them in quotes. I encourage you to not paint in your mind text-only remarks with such stark emotions so readily.

- tye        

Why isn't "like" appropriate?

As has been said, a useful LIKE statement needs wildcards (otherwise it's just testing equality). Not to stray too far OT, but you'd also need to cast your date to a string (using to_char). Basically, my advice (for what it's worth) is to stick with comparisons like <= for dates.

The part about the nls setting is more important. You should insure that your DBIx connection spits out dates in the same format as your other Oracle clients. Who knows, you could be trying to compare these to ISO 8601 format.