support basic stats for column tables

ydb/core/tx/schemeshard/schemeshard_impl.cpp

@@ -7052,7 +7052,18 @@ void TSchemeShard::SendBaseStatsToSA() {
         entry->SetBytesSize(aggregated.DataSize);
         ++count;
     }
-    // TODO: add column tables
+    auto columnTablesPathIds = ColumnTables.GetAllPathIds();
+    for (const auto& pathId : columnTablesPathIds) {
+        const auto& tableInfo = ColumnTables.GetVerified(pathId);
+        const auto& aggregated = tableInfo->Stats.Aggregated;
+        auto* entry = record.AddEntries();
+        auto* entryPathId = entry->MutablePathId();
+        entryPathId->SetOwnerId(pathId.OwnerId);
+        entryPathId->SetLocalId(pathId.LocalPathId);
+        entry->SetRowCount(aggregated.RowCount);
+        entry->SetBytesSize(aggregated.DataSize);
+        ++count;
+    }
 
     TString stats;
     stats.clear();

ydb/core/tx/schemeshard/schemeshard_tables_storage.cpp

@@ -148,4 +148,12 @@ bool TTablesStorage::TTableCreateOperator::InitShardingTablets(const TColumnTabl
     return true;
 }
 
+std::unordered_set<TPathId> TTablesStorage::GetAllPathIds() const {
+    std::unordered_set<TPathId> result;
+    for (const auto& [pathId, _] : Tables) {
+        result.emplace(pathId);
+    }
+    return result;
+}
+
 }

ydb/core/tx/schemeshard/schemeshard_tables_storage.h

@@ -159,6 +159,7 @@ class TTablesStorage {
     void OnRemoveObject(const TPathId& pathId, TColumnTableInfo::TPtr object);
     TColumnTableInfo::TPtr ExtractPtr(const TPathId& id);
 public:
+    std::unordered_set<TPathId> GetAllPathIds() const;
 
     TColumnTablesLayout GetTablesLayout(const std::vector<ui64>& tabletIds) const;