ci/eval: fix stats table

ci/eval/stats.sql

@@ -1,22 +1,35 @@
 CREATE VIEW before AS FROM read_json('data/before-stats.json', map_inference_threshold=-1);
 CREATE VIEW after  AS FROM read_json('data/after-stats.json', map_inference_threshold=-1);
 
-CREATE MACRO aggregate(tbl) AS TABLE SELECT sum(COLUMNS(*)) FROM query_table(tbl);
+CREATE MACRO aggregate(tbl) AS TABLE
+SELECT sum(COLUMNS(*)) FROM query_table(tbl);
 
-CREATE MACRO arrow(i) AS
+CREATE MACRO trimFract(x) AS
 CASE
-  WHEN i > 0 THEN format('↗ {:t,}', i::int)
-  WHEN i < 0 THEN format('↘ {:t,}', -i::int)
+  WHEN x = round(x) THEN format('{:,}', x::bigint)
+  ELSE format('{:,.2f}', round(x, 2))
+END;
+
+CREATE MACRO arrow(x) AS
+CASE
+  WHEN x > 0 THEN format('↗ {}', trimFract(x))
+  WHEN x < 0 THEN format('↘ {}', trimFract(-x))
   ELSE ''
 END;
 
+CREATE MACRO pct(x) AS
+CASE
+  WHEN round(x * 100, 2) = 0 then ''
+  ELSE format('{:.2f}', round(x * 100, 2))
+END;
+
 CREATE TABLE stats AS
 SELECT
   name AS stat,
-  format('{:,}', b.value) AS before,
-  format('{:,}', a.value) AS after,
+  b.value.trimFract() AS before,
+  a.value.trimFract() AS after,
   (a.value - b.value).arrow() AS "Δ",
-  ((1 - b.value/a.value) * 100)::DECIMAL(15,2) AS "Δ%",
+  (a.value/b.value - 1).pct() AS "Δ%",
 FROM (UNPIVOT (from aggregate(before)) ON *) as b
 JOIN (UNPIVOT (from aggregate(after)) ON *) as a USING(name);