Very impressive! Works well, nice UI, informative.<p>After doing a couple exercises what I don't like is the naming convention. Something like "montlymaintenance" or "recommendedby" are just hard to read and type and I'd much rather use snake-case and/or shorter names. Eg. "monthly_maintenance" or "maintenance_per_month" or just "maintenance" if it's explicit enough that it's always per month.<p>Also to me using shorthands for ids is a bit hmm hmm I mean sure you write them a lot so it's useful to spare your fingers when typing queries but "facid" just seems wrong. Again maybe underscore? "fac_id" or even "facility_id".<p>Well that's at least my opinion. Also would it be a better practise to use "timestamptz" instead of "timestamp"? And FYI I had to zoom to 125% because the font was so small on my laptop.
This seems as good of place as any to ask novice-level questions about PostgreSQL. I teach students SQLite and one of the most massive pain points in transitioning to PgSQL is how the latter, in the `WHERE` clause, fails to recognize aliases in the `SELECT` clause, e.g.<p><pre><code> SELECT UPPER(name) AS bigname
FROM people
WHERE bigname = 'JOE';
</code></pre>
<a href="https://stackoverflow.com/questions/38040631/postgresql-does-not-accept-column-alias-in-where-clause" rel="nofollow">https://stackoverflow.com/questions/38040631/postgresql-does...</a><p>Apparently this is the SQL standard, which PgSQL seems to do a better job of following than SQLite, but I'm at a loss to understand why this computation is particularly problematic for PgSQL (or any variant) to adopt? Unlike other SQL standard rules that PgSQL follows that SQLite/MySQL doesn't (such as forbidding the selection of column names that aren't being GROUPed by in a GROUP BY clause), this strictness seems to be all inconvenience.
Cool.SQL Zoo <a href="http://sqlzoo.net/" rel="nofollow">http://sqlzoo.net/</a> is also worth recommending for beginners.
Neat - thanks for sharing!<p>In the SQL MOOC space, you can also check out <a href="https://academy.vertabelo.com" rel="nofollow">https://academy.vertabelo.com</a>.<p>If other people have resources, please share them out, I think this is an area where spreading the knowledge is particularly useful to most developers.
Great idea, does what it should and can be extended to cover a lot more. Keep up the great work.<p>First time looking at it I thought I was on a official Ubuntu site, what a font and color can do to a branding is fascinating.
Did a few exercises and seems nice. An improvement would be if hints included links to PostgreSQL documentation, would make it easier for beginners to find good information.
A suggestion: repeat the table names on every exercise in the description. I had been going trough them casually - and always forgot what the table name was and had to go back or press the "show answer" button.