What:
Use the github.com/jackc/pgx postgresql driver in place of
github.com/lib/pq.
Why:
github.com/lib/pq has some problems with error handling and context
cancellations (i.e. it might even issue queries or DML statements more
than once! see https://github.com/lib/pq/issues/939). The
github.com/jackx/pgx library appears not to have these problems, and
also appears to be better engineered and implemented (in particular, it
doesn't use "exceptions by panic"). It should also give us some
performance improvements in some cases, and even more so if we can use
it directly instead of going through the database/sql layer.
Change-Id: Ia696d220f340a097dee9550a312d37de14ed2044
This ensures that rows are closed to avoid leaks.
Also verifies that Err() is called, to ensure that no
error is left behind.
Change-Id: Idd1bec9bf479f40021da67b2c80ce83033149469
* Plumbs the limit through all backends ensuring they don't do
unnecessary work.
* Don't arbitrarily limit at the backend with hardcoded defaults. The
limit will be set by the caller.
Prior to this change the code on recursive in some backends would do 10k
results from the database and then only return the first 1k (throwing
out 9k of them).
Prior to this change some backends had no limit at all (e.g. redis).
Change-Id: I1f327eefe095776d123dd11362cd00994c22efdf
