Aggregate stats for partition tables

input/postgres/relation_stats.go

@@ -20,10 +20,7 @@ locked_relids_with_parents AS (
 	UNION SELECT relid FROM locked_relids
 )
 SELECT c.oid,
-			 COALESCE(pg_catalog.pg_table_size(c.oid), 0) +
-			 COALESCE((SELECT pg_catalog.sum(pg_catalog.pg_table_size(inhrelid))
-			    FROM pg_catalog.pg_inherits
-				 WHERE inhparent = c.oid), 0) AS size_bytes,
+			 COALESCE(pg_catalog.pg_table_size(c.oid), 0) AS size_bytes,
 			 CASE c.reltoastrelid WHEN NULL THEN 0 ELSE COALESCE(pg_catalog.pg_total_relation_size(c.reltoastrelid), 0) END AS toast_bytes,
 			 COALESCE(pg_stat_get_numscans(c.oid), 0) AS seq_scan,
 			 COALESCE(pg_stat_get_tuples_returned(c.oid), 0) AS seq_tup_read,

output/transform/merge_partition_sizes.go

@@ -0,0 +1,56 @@
+package transform
+
+import (
+	snapshot "github.com/pganalyze/collector/output/pganalyze_collector"
+	"github.com/pganalyze/collector/state"
+)
+
+func mergePartitionSizes(s snapshot.FullSnapshot, newState state.PersistedState, ts state.TransientState, databaseOidToIdx OidToIdx) snapshot.FullSnapshot {
+	for idx, info := range s.IndexInformations {
+		rel := s.RelationInformations[info.RelationIdx]
+		if !rel.HasParentRelation || rel.PartitionBoundary == "" {
+			continue
+		}
+		for parentIdx, pi := range s.IndexInformations {
+			if pi.RelationIdx != rel.ParentRelationIdx {
+				continue
+			}
+			if info.IndexType == pi.IndexType && info.IsUnique == pi.IsUnique && intArrayEqual(info.Columns, pi.Columns) {
+				s.IndexStatistics[parentIdx].SizeBytes += s.IndexStatistics[idx].SizeBytes
+				break
+			}
+		}
+	}
+
+	for idx, rel := range s.RelationInformations {
+		if !rel.HasParentRelation || rel.PartitionBoundary == "" {
+			continue
+		}
+		stat := s.RelationStatistics[idx]
+		parent := s.RelationStatistics[rel.ParentRelationIdx]
+		parent.NTupIns += stat.NTupIns
+		parent.NTupUpd += stat.NTupUpd
+		parent.NTupDel += stat.NTupDel
+		parent.NTupHotUpd += stat.NTupHotUpd
+		parent.NLiveTup += stat.NLiveTup
+		parent.NDeadTup += stat.NDeadTup
+		parent.SizeBytes += stat.SizeBytes
+		parent.ToastSizeBytes += stat.ToastSizeBytes
+		parent.CachedDataBytes += stat.CachedDataBytes
+		parent.CachedToastBytes += stat.CachedToastBytes
+	}
+
+	return s
+}
+
+func intArrayEqual(a []int32, b []int32) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i, v := range a {
+		if v != b[i] {
+			return false
+		}
+	}
+	return true
+}

output/transform/postgres.go

@@ -23,6 +23,7 @@ func transformPostgres(s snapshot.FullSnapshot, newState state.PersistedState, d
 	s = transformPostgresBackendCounts(s, transientState, roleOidToIdx, databaseOidToIdx)
 	s = transformPostgresExtensions(s, transientState, databaseOidToIdx)
 	s = transformPostgresBufferCache(s, transientState, databaseOidToIdx)
+	s = mergePartitionSizes(s, newState, transientState, databaseOidToIdx)
 
 	return s
 }

output/transform/postgres_relations.go

@@ -253,20 +253,17 @@ func transformPostgresRelations(s snapshot.FullSnapshot, newState state.Persiste
 
 			// Statistic
 			if diffedSchemaStatsExist {
-				indexStats, exists := diffedSchemaStats.IndexStats[index.IndexOid]
-				if exists {
-					statistic := snapshot.IndexStatistic{
-						IndexIdx:    indexIdx,
-						SizeBytes:   indexStats.SizeBytes,
-						IdxScan:     indexStats.IdxScan,
-						IdxTupRead:  indexStats.IdxTupRead,
-						IdxTupFetch: indexStats.IdxTupFetch,
-						IdxBlksRead: indexStats.IdxBlksRead,
-						IdxBlksHit:  indexStats.IdxBlksHit,
-						CachedBytes: index.CachedBytes,
-					}
-					s.IndexStatistics = append(s.IndexStatistics, &statistic)
-				}
+				indexStats := diffedSchemaStats.IndexStats[index.IndexOid]
+				s.IndexStatistics = append(s.IndexStatistics, &snapshot.IndexStatistic{
+					IndexIdx:    indexIdx,
+					SizeBytes:   indexStats.SizeBytes,
+					IdxScan:     indexStats.IdxScan,
+					IdxTupRead:  indexStats.IdxTupRead,
+					IdxTupFetch: indexStats.IdxTupFetch,
+					IdxBlksRead: indexStats.IdxBlksRead,
+					IdxBlksHit:  indexStats.IdxBlksHit,
+					CachedBytes: index.CachedBytes,
+				})
 			}
 		}
 	}