Remove "limit 10" from the default SQL queries

[xandrew-lynx]

The result is limited on display anyways. I delete it every single time and it's annoying. Any drawback of removing these?

[xandrew-lynx]

(Except when I forget to remove it and scratch my head on why something is weird downstream... :/ )

[darabos]

Ah, yes please! The counter argument was (as I recall) that "persist: yes" is also a default. So even though in getTableOutput we only fetch the first 10 lines, the backend may still end up computing and storing a lot of data unnecessarily.

How about we set "persist: no" as the default? I think the counter argument for that was that Spark at the time didn't handle long chains well. But I'm just upgrading to Spark 3. Hopefully it's a solved problem by now. A longer chain even allows for better optimization. (E.g. maybe you don't need to compute some intermediate data if you don't need it in the end.) And also we are not building long SQL chains all the time. You can turn on "persist" when needed.

[xandrew-lynx]

Sounds good to me. Especially as persisting also messes up ordering when the user adds "order by". :/

[darabos]

Done in #220. Forgot to close it.