For me, only “a hotel” and “an SQL query” sound correct here

(Edit: I just realised this might be a dialect thing. I say “ess cue ell” and not “sequel”, and “hoe tell” rather than “otel”. Australian accent)

a ho.tel

an oh.tel or o.tel (is it still spoken somewhere like this?)

The confusion arrives for words like "herb" depending upon whether the place uses F or C for temperature ;-)