From e192ca3300b63c18b211be9355639d52fc602b49 Mon Sep 17 00:00:00 2001
From: Graham McIntire <graham@mcintire.me>
Date: Fri, 24 Apr 2026 16:39:57 -0500
Subject: [PATCH] fix(weather): analyze_all skip_recent check reads both
 analyze timestamps
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pg_stat_user_tables tracks two timestamps — `last_autoanalyze`
is only bumped by the autovacuum daemon, while `last_analyze` is
bumped by manual ANALYZE statements (including the ones our Task
issues). The previous query only filtered on `last_autoanalyze`,
so on a re-run within the skip_recent window every manually-
analyzed table came back for another ANALYZE pass.

Uses `GREATEST(last_analyze, last_autoanalyze)` so fresh manual
analyses count as recent.
---
 lib/microwaveprop/weather.ex | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/microwaveprop/weather.ex b/lib/microwaveprop/weather.ex
index 5b003727..3dd58492 100644
--- a/lib/microwaveprop/weather.ex
+++ b/lib/microwaveprop/weather.ex
@@ -434,12 +434,18 @@ defmodule Microwaveprop.Weather do
   def analyze_all(opts \\ []) do
     skip_recent = Keyword.get(opts, :skip_recent_seconds, 6 * 3600)
 
+    # `last_autoanalyze` is only set by the autovacuum daemon;
+    # `last_analyze` is set by manual ANALYZE (including our Task
+    # below). Take the newer of the two — otherwise a re-run within
+    # `skip_recent` would re-analyze everything we just did.
     q = """
     SELECT relname
     FROM pg_stat_user_tables
     WHERE schemaname = 'public'
-      AND (last_autoanalyze IS NULL
-           OR last_autoanalyze < now() - ($1 || ' seconds')::interval)
+      AND COALESCE(
+        GREATEST(last_analyze, last_autoanalyze),
+        'epoch'::timestamptz
+      ) < now() - ($1 || ' seconds')::interval
     ORDER BY n_live_tup ASC
     """