They mentioned pronunciation : 'S-Q-L' vs 'sequel'. I've always pronounced it S-Q-L. The lecturer implies there's no right answer, that 'sequel' is historical but 'S-Q-L' is preferred for international use.
The annoying thing, though, is that in writing a choice has to be made. If someone pronounces it 'S-Q-L' then to read 'a SQL query' is weird -- it should say 'an SQL query'. And vice versa for someone who pronounces it 'sequel'. 'an sequel query' isn't right.
So, in writing, what is correct? 'An sql query' or 'a sql query'?