feat: implement histogram_quantile in PromQL (#2651)

* add to planner Signed-off-by: Ruihang Xia <waynestxia@gmail.com> * impl evaluate_array Signed-off-by: Ruihang Xia <waynestxia@gmail.com> * compute quantile Signed-off-by: Ruihang Xia <waynestxia@gmail.com> * fix clippy Signed-off-by: Ruihang Xia <waynestxia@gmail.com> * fix required input ordering Signed-off-by: Ruihang Xia <waynestxia@gmail.com> * add more tests Signed-off-by: Ruihang Xia <waynestxia@gmail.com> * todo to fixme Signed-off-by: Ruihang Xia <waynestxia@gmail.com> --------- Signed-off-by: Ruihang Xia <waynestxia@gmail.com>
2026-01-06 21:32:58 +00:00 · 2023-10-25 16:19:30 +08:00
parent e8adaaf5f7
commit f08a35d6b9
7 changed files with 693 additions and 113 deletions
--- a/tests/cases/standalone/common/promql/simple_histogram.sql
+++ b/tests/cases/standalone/common/promql/simple_histogram.sql
@@ -0,0 +1,134 @@
+-- from prometheus/promql/testdata/histograms.test
+-- cases related to metric `testhistogram_bucket`
+
+create table histogram_bucket (
+    ts timestamp time index,
+    le string,
+    s string,
+    val double,
+    primary key (s, le),
+);
+
+insert into histogram_bucket values
+    (3000000, "0.1", "positive", 50),
+    (3000000, ".2", "positive", 70),
+    (3000000, "1e0", "positive", 110),
+    (3000000, "+Inf", "positive", 120),
+    (3000000, "-.2", "negative", 10),
+    (3000000, "-0.1", "negative", 20),
+    (3000000, "0.3", "negative", 20),
+    (3000000, "+Inf", "negative", 30);
+
+-- Quantile too low.
+-- SQLNESS SORT_RESULT 3 1
+tql eval (3000, 3000, '1s') histogram_quantile(-0.1, histogram_bucket);
+
+-- Quantile too high.
+-- SQLNESS SORT_RESULT 3 1
+tql eval (3000, 3000, '1s') histogram_quantile(1.01, histogram_bucket);
+
+-- Quantile invalid.
+-- SQLNESS SORT_RESULT 3 1
+tql eval (3000, 3000, '1s') histogram_quantile(NaN, histogram_bucket);
+
+-- Quantile value in lowest bucket, which is positive.
+tql eval (3000, 3000, '1s') histogram_quantile(0, histogram_bucket{s="positive"});
+
+-- Quantile value in lowest bucket, which is negative.
+tql eval (3000, 3000, '1s') histogram_quantile(0, histogram_bucket{s="negative"});
+
+-- Quantile value in highest bucket.
+-- SQLNESS SORT_RESULT 3 1
+tql eval (3000, 3000, '1s') histogram_quantile(1, histogram_bucket);
+
+-- Finally some useful quantiles.
+-- SQLNESS SORT_RESULT 3 1
+tql eval (3000, 3000, '1s') histogram_quantile(0.2, histogram_bucket);
+
+-- SQLNESS SORT_RESULT 3 1
+tql eval (3000, 3000, '1s') histogram_quantile(0.5, histogram_bucket);
+
+-- SQLNESS SORT_RESULT 3 1
+tql eval (3000, 3000, '1s') histogram_quantile(0.8, histogram_bucket);
+
+-- More realistic with rates.
+-- This case doesn't contains value because other point are not inserted.
+-- quantile with rate is covered in other cases
+tql eval (3000, 3000, '1s') histogram_quantile(0.2, rate(histogram_bucket[5m]));
+
+drop table histogram_bucket;
+
+-- cases related to `testhistogram2_bucket`
+create table histogram2_bucket (
+    ts timestamp time index,
+    le string,
+    val double,
+    primary key (le),
+);
+
+insert into histogram2_bucket values
+    (0, "0", 0),
+    (300000, "0", 0),
+    (600000, "0", 0),
+    (900000, "0", 0),
+    (1200000, "0", 0),
+    (1500000, "0", 0),
+    (1800000, "0", 0),
+    (2100000, "0", 0),
+    (2400000, "0", 0),
+    (2700000, "0", 0),
+    (0, "2", 1),
+    (300000, "2", 2),
+    (600000, "2", 3),
+    (900000, "2", 4),
+    (1200000, "2", 5),
+    (1500000, "2", 6),
+    (1800000, "2", 7),
+    (2100000, "2", 8),
+    (2400000, "2", 9),
+    (2700000, "2", 10),
+    (0, "4", 2),
+    (300000, "4", 4),
+    (600000, "4", 6),
+    (900000, "4", 8),
+    (1200000, "4", 10),
+    (1500000, "4", 12),
+    (1800000, "4", 14),
+    (2100000, "4", 16),
+    (2400000, "4", 18),
+    (2700000, "4", 20),
+    (0, "6", 3),
+    (300000, "6", 6),
+    (600000, "6", 9),
+    (900000, "6", 12),
+    (1200000, "6", 15),
+    (1500000, "6", 18),
+    (1800000, "6", 21),
+    (2100000, "6", 24),
+    (2400000, "6", 27),
+    (2700000, "6", 30),
+    (0, "+Inf", 3),
+    (300000, "+Inf", 6),
+    (600000, "+Inf", 9),
+    (900000, "+Inf", 12),
+    (1200000, "+Inf", 15),
+    (1500000, "+Inf", 18),
+    (1800000, "+Inf", 21),
+    (2100000, "+Inf", 24),
+    (2400000, "+Inf", 27),
+    (2700000, "+Inf", 30);
+
+-- Want results exactly in the middle of the bucket.
+tql eval (420, 420, '1s') histogram_quantile(0.166, histogram2_bucket);
+
+tql eval (420, 420, '1s') histogram_quantile(0.5, histogram2_bucket);
+
+tql eval (420, 420, '1s') histogram_quantile(0.833, histogram2_bucket);
+
+tql eval (2820, 2820, '1s') histogram_quantile(0.166, rate(histogram2_bucket[15m]));
+
+tql eval (2820, 2820, '1s') histogram_quantile(0.5, rate(histogram2_bucket[15m]));
+
+tql eval (2820, 2820, '1s') histogram_quantile(0.833, rate(histogram2_bucket[15m]));
+
+drop table histogram2_bucket;