Weigh-ins: Garmin's document has no samplePk and gives kilograms, the live
service sends a samplePk and grams. A weigh-in now takes its id from
samplePk or else its own GMT instant, reads each mass by magnitude (above
1000 is grams), and is written whole or not at all: a missing weight, a
missing instant or one implausible value drops every row of it, counted
on the wide event by reason.
Refused resources: a lasting 4xx on one resource (a cycle summary for an
account that tracks no cycle) is noted once on the progress column,
counts as done for the backfill, is skipped by the hourly sync and is
listed in the card's details. It no longer holds the backfill open or
turns the connection red. The cycle leg never parks the connection,
whatever it is refused with.
Backfill: weigh-ins walk back to the start of Garmin Connect on their
own, so history before the first watch day and a scale-only account
arrive. Progress and the completion stamp are written only while the
connection the slice started on is still the stored one.
Key: connect sends the key to the one service the person picks (Garmin
Connect or Garmin Connect China), never to both. A parked key is asked
about again once a day with a single token exchange and reconnected when
Garmin accepts it. The key's end is read from the token's own iat and
exp, an estimate the key outlived is cleared after an accepted exchange,
and the validity can be corrected from the card's menu (PATCH
/api/garmin/key-expiry, with the day the key was created) without
pasting it again.
Sync: an incremental run reaches back to the last successful sync, up to
a year, so an outage longer than the 30-day window leaves no gap; a night
Garmin no longer reports (deleted, or turned into a nap) is retired.
Card: connect errors are translated from meta.errorCode in every locale.
Types: BODY_BATTERY, STRESS_LEVEL, TRAINING_READINESS and
ACUTE_TRAINING_LOAD get source ladders of their own (the device or the
bridge first, then the hand-entered sources in their usual order), join
the ranked types and the provenance picker, and the recovery-empty
description names them.
The canonical-source pick grouped the window to (type, day, source),
chose each day's source with DISTINCT ON, and joined the choices back to
the rows. Whether that join ran as a hash join or as a nested loop that
rescanned the whole pick for every row was the planner's call, made from
table statistics. On a measurements table without them (a new install,
or an import still under the autoanalyze threshold) it estimated one row
on each side and took the nested loop.
Binding the request's clock as a parameter instead of reading NOW()
flipped which side of that loop the pick landed on: the analytics read
over 6,000 freshly written blood-pressure rows went from 1.6 s to 8.4 s,
and the demo seed's dashboard headline to 20 s. On a ten-year account
without statistics the 90-day read took 4 s with either clock and the
all-time read ran past two minutes.
The pick is now one window function over one scan: FIRST_VALUE of the
source per (type, UTC day) in ladder order, keeping the rows of that
source. Same rows, same order of preference, so every day keeps its
source; the parity suite against the DISTINCT ON statement holds that.
The analytics read on the fixture above takes about 0.1 s, the headline
0.4 s. On the analysed ten-year account the 90-day and all-time reads
are as fast as the join was, and they no longer depend on statistics.
The rows carry one extra column, canonical_source; every reader selects
its columns by name.
A new integration test runs every reader shape under EXPLAIN ANALYZE on
a table with no statistics and bounds the rows the plan produces or
discards per row seeded. The statement count never moved, so a statement
budget could not see this; the join measured 200 to 8,600 row visits
per row seeded and the window stays at 4.
Readers that tag a cell as a closed block no longer import the
invalidation module, which several tests replace wholesale. The cache
route test counts the slice's pre-fold cell apart from the route's two
cells, and the provenance test reads the shared pick's ORDER BY over its
grouped rows.
A read-only view per metric and UTC day: every source with readings, its
day value, its place in the person's source priority, and which source
the charts use with the reason. A second card lines two sources up over
30, 90 or 365 days. The pick is explained from the rank the canonical
SQL returns, so the page cannot disagree with the charts. Linked from
the metric pages and from Settings > Source priority.
Marc-André Bombeck