Tbh I usually see teachers worried about joins but its the group by/having clauses that I always watched people struggle with (at least, writing it).
Ofc that might just be the emphasis on joins makes group by the next lowest hanging fruit
Ofc that might just be the emphasis on joins makes group by the next lowest hanging fruit
Urban Dictionary (https://www.urbandictionary.com) or even just typing something like "what does tbh mean?" into your preferred search engine will often help you find likely interpretations of unknown abbreviations, in my experience.
I mean, that's what they did.