Use variant_combinations for query-level variant filtering

Replace array containment checks on large tables with subqueries
against the small variant_combinations table (2K rows), then filter
by integer variant_combination_id.

Benchmarked on staging:
- TestReportExcludeVariants: 1,167ms → 55ms (21x faster)
- TestsByNURPAndStandardDeviation: 505ms → 223ms (2.3x faster)
- PlatformInfraSuccess: 508ms → 346ms (1.5x faster)
- Collapsed matview filter: 1,158ms → 500ms (2.3x faster)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: mstaeble

pkg/db/query/misc_queries.go

@@ -1,6 +1,7 @@
 package query
 
 import (
+	"database/sql"
 	"fmt"
 	"time"
 
@@ -28,20 +29,25 @@ func PlatformInfraSuccess(dbc *db.DB, platforms sets.String, period string) (map
 		return nil, fmt.Errorf("unknown period %s", period)
 	}
 
-	raw := dbc.DB.Table(table).
-		Select("*, unnest(variants) as variant").
-		Where("name = ?", testidentification.NewInfrastructureTestName)
-
 	var sqlResults []struct {
 		Variant        string
 		PassPercentage float64
 	}
-	q := dbc.DB.Table("(?) as results", raw).
-		Select(`
-			variant,
-			SUM(current_successes) * 100.0 / NULLIF(SUM(current_runs), 0) AS pass_percentage`).
-		Where("variant in ?", platforms.List()).
-		Group("variant").Scan(&sqlResults)
+	q := dbc.DB.Raw(fmt.Sprintf(`
+		WITH target_variants AS (
+			SELECT vc.id, v.variant
+			FROM variant_combinations vc, unnest(vc.variants) AS v(variant)
+			WHERE v.variant IN @platforms
+		)
+		SELECT tv.variant,
+			SUM(m.current_successes) * 100.0 / NULLIF(SUM(m.current_runs), 0) AS pass_percentage
+		FROM %s m
+		JOIN target_variants tv ON m.variant_combination_id = tv.id
+		WHERE m.name = @testname
+		GROUP BY tv.variant`, table),
+		sql.Named("platforms", platforms.List()),
+		sql.Named("testname", testidentification.NewInfrastructureTestName),
+	).Scan(&sqlResults)
 
 	for _, r := range sqlResults {
 		results[r.Variant] = r.PassPercentage

pkg/db/query/test_queries.go

@@ -113,7 +113,10 @@ func TestReportsByVariant(
 	// Query and group by variant:
 	var testReports []api.Test
 	q := `
-WITH results AS (
+WITH excluded_vc AS (
+    SELECT id FROM variant_combinations WHERE @excluded && variants
+),
+results AS (
     SELECT name,
            release,
            sum(current_runs)       AS current_runs,
@@ -127,7 +130,7 @@ WITH results AS (
            unnest(variants)        AS variant
     FROM prow_test_report_7d_matview
 	WHERE release = @release AND name ~* @testsubstrings
-          AND NOT(variants is not null and @excluded && variants)
+          AND variant_combination_id NOT IN (SELECT id FROM excluded_vc)
     GROUP BY name, release, variant
 )
 SELECT *,
@@ -169,7 +172,10 @@ func TestReportExcludeVariants(dbc *db.DB, release, testName string, excludeVari
 
 	// Query and group by variant:
 	var testReport api.Test
-	q := `WITH results AS (
+	q := `WITH excluded_vc AS (
+    SELECT id FROM variant_combinations WHERE @excluded && variants
+),
+results AS (
     SELECT name,
            release,
            sum(current_runs)       AS current_runs,
@@ -182,7 +188,7 @@ func TestReportExcludeVariants(dbc *db.DB, release, testName string, excludeVari
            sum(previous_flakes)    AS previous_flakes
     FROM prow_test_report_7d_matview
     WHERE release = @release AND name = @testname
-          AND NOT(variants is not null and @excluded && variants)
+          AND variant_combination_id NOT IN (SELECT id FROM excluded_vc)
     GROUP BY name, release
 ) SELECT *, %s FROM results;`
 
@@ -243,7 +249,7 @@ func TestsByNURPAndStandardDeviation(dbc *db.DB, release, table string) *gorm.DB
 			(current_pass_percentage - passing_average) AS delta_from_passing_average,
 			(current_flake_percentage - flake_average) AS delta_from_flake_average`).
 		Where(`release = ?`, release).
-		Where(fmt.Sprintf("NOT ('never-stable'=any(%s.variants))", table))
+		Where("variant_combination_id NOT IN (SELECT id FROM variant_combinations WHERE 'never-stable' = any(variants))")
 }
 
 func TestOutputs(dbc *db.DB, release, test string, includedVariants, excludedVariants []string, quantity int) ([]api.TestOutput, error) {

pkg/db/views.go

@@ -372,10 +372,11 @@ var CollapsedVariantExclusions = []string{"never-stable", "aggregated"}
 var testReportCollapsedMatView = buildCollapsedMatViewSQL()
 
 func buildCollapsedMatViewSQL() string {
-	var clauses []string
-	for _, v := range CollapsedVariantExclusions {
-		clauses = append(clauses, fmt.Sprintf("NOT ('%s' = any(variants))", v))
+	quotedExclusions := make([]string, len(CollapsedVariantExclusions))
+	for i, v := range CollapsedVariantExclusions {
+		quotedExclusions[i] = fmt.Sprintf("'%s'", v)
 	}
+	excludedArray := "ARRAY[" + strings.Join(quotedExclusions, ",") + "]"
 	return `
 SELECT suite_name, name, id, jira_component, jira_component_id, release,
     SUM(current_runs)::bigint AS current_runs,
@@ -388,7 +389,9 @@ SELECT suite_name, name, id, jira_component, jira_component_id, release,
     SUM(previous_flakes)::bigint AS previous_flakes,
     (array_agg(open_bugs))[1] AS open_bugs
 FROM |||SOURCE|||
-WHERE ` + strings.Join(clauses, "\n  AND ") + `
+WHERE variant_combination_id NOT IN (
+    SELECT id FROM variant_combinations WHERE ` + excludedArray + ` && variants
+)
 GROUP BY suite_name, name, id, jira_component, jira_component_id, release
 `
 }