PR from branch users/eivanov89/KIKIMR-5850-tablet-flat-minor-cleanup

KIKIMR-5850: cleanup row cooker

KIKIMR-5850: rename block to maxBlobSize

ref:6e000b02c4b6ff51864ed9368127ea346c6bc005

25 files changed, 216 insertions, 214 deletions

diff --git a/ydb/core/tablet_flat/flat_executor.cpp b/ydb/core/tablet_flat/flat_executor.cpp
index 59afc462158..e38dda8373c 100644
--- a/ydb/core/tablet_flat/flat_executor.cpp
+++ b/ydb/core/tablet_flat/flat_executor.cpp
@@ -3979,7 +3979,7 @@ ui64 TExecutor::BeginCompaction(THolder<NTable::TCompactionParams> params)
         pageGroup.PageSize = policy->MinDataPageSize;
 
         writeGroup.Cache = Max(family->Cache, cache);
-        writeGroup.Block = NBlockIO::BlockSize;
+        writeGroup.MaxBlobSize = NBlockIO::BlockSize;
         writeGroup.Channel = room->Main;
         addChannel(room->Main);
 
diff --git a/ydb/core/tablet_flat/flat_sausage_writer.h b/ydb/core/tablet_flat/flat_sausage_writer.h
index c7cda9e2a47..43fda7ed8a8 100644
--- a/ydb/core/tablet_flat/flat_sausage_writer.h
+++ b/ydb/core/tablet_flat/flat_sausage_writer.h
@@ -9,8 +9,8 @@ namespace NPageCollection {
 
     class TWriter {
     public:
-        TWriter(TCookieAllocator &cookieAllocator, ui8 channel, ui32 block)
-            : Block(block)
+        TWriter(TCookieAllocator &cookieAllocator, ui8 channel, ui32 maxBlobSize)
+            : MaxBlobSize(maxBlobSize)
             , Channel(channel)
             , CookieAllocator(cookieAllocator)
             , Record(cookieAllocator.GroupBy(channel))
@@ -26,16 +26,16 @@ namespace NPageCollection {
         ui32 AddPage(const TArrayRef<const char> body, ui32 type)
         {
             for (size_t offset = 0; offset < body.size(); ) {
-                if (Buffer.capacity() == 0 && Block != Max<ui32>())
-                    Buffer.reserve(Min(Block, ui32(16 * 1024 * 1024)));
+                if (Buffer.capacity() == 0 && MaxBlobSize != Max<ui32>())
+                    Buffer.reserve(Min(MaxBlobSize, ui32(16 * 1024 * 1024)));
 
-                auto piece = Min(body.size() - offset, Block - Buffer.size());
+                auto piece = Min(body.size() - offset, MaxBlobSize - Buffer.size());
                 auto chunk = body.Slice(offset, piece);
 
                 Buffer.append(chunk.data(), chunk.size());
                 offset += piece;
 
-                if (Buffer.size() >= Block) Flush();
+                if (Buffer.size() >= MaxBlobSize) Flush();
             }
 
             return Record.Push(type, body);
@@ -95,7 +95,7 @@ namespace NPageCollection {
         }
 
     public:
-        const ui32 Block = Max<ui32>();
+        const ui32 MaxBlobSize = Max<ui32>();
         const ui8 Channel = Max<ui8>();
     private:
         TString Buffer;
diff --git a/ydb/core/tablet_flat/flat_writer_blocks.h b/ydb/core/tablet_flat/flat_writer_blocks.h
index b35da85e166..6f7bca85e43 100644
--- a/ydb/core/tablet_flat/flat_writer_blocks.h
+++ b/ydb/core/tablet_flat/flat_writer_blocks.h
@@ -98,7 +98,7 @@ namespace NWriter {
 
         NPageCollection::TLargeGlobId CutToChunks(TArrayRef<const char> body)
         {
-            return Cone->Put(0, Channel, body, Writer.Block);
+            return Cone->Put(0, Channel, body, Writer.MaxBlobSize);
         }
 
     private:
diff --git a/ydb/core/tablet_flat/flat_writer_bundle.h b/ydb/core/tablet_flat/flat_writer_bundle.h
index d489e51e9df..761d3243326 100644
--- a/ydb/core/tablet_flat/flat_writer_bundle.h
+++ b/ydb/core/tablet_flat/flat_writer_bundle.h
@@ -32,9 +32,10 @@ namespace NWriter {
 
             Blocks.resize(Groups.size() + 1);
             for (size_t group : xrange(Groups.size())) {
-                Blocks[group].Reset(new TBlocks(this, Groups[group].Channel, Groups[group].Cache, Groups[group].Block));
+                Blocks[group].Reset(
+                    new TBlocks(this, Groups[group].Channel, Groups[group].Cache, Groups[group].MaxBlobSize));
             }
-            Blocks[Groups.size()].Reset(new TBlocks(this, conf.OuterChannel, none, Groups[0].Block));
+            Blocks[Groups.size()].Reset(new TBlocks(this, conf.OuterChannel, none, Groups[0].MaxBlobSize));
 
             Growth = new NTable::TScreen::TCook;
         }
@@ -60,7 +61,7 @@ namespace NWriter {
 
         NPageCollection::TLargeGlobId WriteExtra(TArrayRef<const char> body) noexcept
         {
-            return Put(/* data cookieRange */ 1, ExtraChannel, body, Groups[0].Block);
+            return Put(/* data cookieRange */ 1, ExtraChannel, body, Groups[0].MaxBlobSize);
         }
 
     private:
diff --git a/ydb/core/tablet_flat/flat_writer_conf.h b/ydb/core/tablet_flat/flat_writer_conf.h
index 02dfdfdfda6..efeb9440c69 100644
--- a/ydb/core/tablet_flat/flat_writer_conf.h
+++ b/ydb/core/tablet_flat/flat_writer_conf.h
@@ -23,7 +23,7 @@ namespace NWriter {
         struct TGroup {
             ui8 Channel = 1;              /* Data channel for page collection */
             ECache Cache = ECache::None;  /* Keep data pages in memory */
-            ui32 Block = 8 * 1024 * 1024; /* Page collection max blob size */
+            ui32 MaxBlobSize = 8 * 1024 * 1024; /* Page collection max blob size */
         };
 
         ui8 BlobsChannel = 1;   /* Channel for external blobs */
diff --git a/ydb/core/tablet_flat/test/libs/rows/cook.h b/ydb/core/tablet_flat/test/libs/rows/cook.h
index a6fb2b48084..94a2358bb97 100644
--- a/ydb/core/tablet_flat/test/libs/rows/cook.h
+++ b/ydb/core/tablet_flat/test/libs/rows/cook.h
@@ -18,10 +18,11 @@ namespace NTest {
             Y_VERIFY(!*row, "Cooked row hasn't been grabbed to TRow");
         }
 
-        template<typename ...TArgs>
-        inline TCookRow& Do(NTable::TTag tag, TArgs&& ...args)
+        template<typename TVal>
+        inline TCookRow& Do(NTable::TTag tag, TVal&& val)
         {
-            return row.Do(tag, std::forward<TArgs>(args)...), *this;
+            row.Do(tag, std::move(val));
+            return *this;
         }
 
         TRow operator *() noexcept
@@ -33,9 +34,9 @@ namespace NTest {
         TRow row;
     };
 
-    class TNatural {
+    class TSchemedCookRow {
     public:
-        TNatural(const TRowScheme &scheme, TPos skip = 0)
+        TSchemedCookRow(const TRowScheme &scheme, TPos skip = 0)
             : On(skip), Scheme(scheme) { }
 
         inline TRow operator*() noexcept
@@ -43,18 +44,18 @@ namespace NTest {
             return std::move(Row);
         }
 
-        TNatural& To(TPos to) noexcept
+        TSchemedCookRow& To(TPos to) noexcept
         {
-            if(to < On || to >= Scheme.Cols.size()) {
-
-                Y_FAIL("TNatural row builder skip position is out of range");
+            if (to < On || to >= Scheme.Cols.size()) {
+                Y_FAIL("TSchemedCookRow row builder skip position is out of range");
             }
 
-            return On = to, *this;
+            On = to;
+            return *this;
         }
 
         template<typename TVal, typename ...TArgs>
-        inline TNatural& Col(const TVal &val, TArgs&&...args)
+        inline TSchemedCookRow& Col(const TVal &val, TArgs&&...args)
         {
             if (On >= Scheme.Cols.size()) {
                 Y_FAIL("NO more columns left in row scheme");
diff --git a/ydb/core/tablet_flat/test/libs/table/model/keys.h b/ydb/core/tablet_flat/test/libs/table/model/keys.h
index 7dec47e39b6..56f7f711870 100644
--- a/ydb/core/tablet_flat/test/libs/table/model/keys.h
+++ b/ydb/core/tablet_flat/test/libs/table/model/keys.h
@@ -31,7 +31,7 @@ namespace NTest {
 
         TRow Make(ui64 seq, bool hole) noexcept override
         {
-            TNatural row(*Scheme);
+            TSchemedCookRow row(*Scheme);
 
             auto &bucket = Buckets[seq % Buckets.size()];
             auto name = TStrGen(Rnd).Do(20 + Rnd.GenRand64() % 30);
diff --git a/ydb/core/tablet_flat/test/libs/table/model/large.h b/ydb/core/tablet_flat/test/libs/table/model/large.h
index 6dfb4d6af98..025d8adfbc9 100644
--- a/ydb/core/tablet_flat/test/libs/table/model/large.h
+++ b/ydb/core/tablet_flat/test/libs/table/model/large.h
@@ -25,7 +25,7 @@ namespace NTest {
         {
             const ui64 up = hole ? 0 : 1;
 
-            TNatural row(*Scheme);
+            TSchemedCookRow row(*Scheme);
 
             {
                 Sub[0] += up, row.Col(Seq * 3 + 7, ui32(Seq + 10), Sub[0]);
diff --git a/ydb/core/tablet_flat/test/libs/table/model/small.h b/ydb/core/tablet_flat/test/libs/table/model/small.h
index d1b0cdfca25..32ef386cf18 100644
--- a/ydb/core/tablet_flat/test/libs/table/model/small.h
+++ b/ydb/core/tablet_flat/test/libs/table/model/small.h
@@ -23,7 +23,7 @@ namespace NTest {
 
         TRow Make(ui64 seq, bool hole) noexcept override
         {
-            TNatural row(*Scheme);
+            TSchemedCookRow row(*Scheme);
 
             row.Col(seq, (Saved += hole ? 0 : 1));
 
diff --git a/ydb/core/tablet_flat/test/libs/table/test_dbase.h b/ydb/core/tablet_flat/test/libs/table/test_dbase.h
index fd931a54839..06bede14c9b 100644
--- a/ydb/core/tablet_flat/test/libs/table/test_dbase.h
+++ b/ydb/core/tablet_flat/test/libs/table/test_dbase.h
@@ -131,7 +131,7 @@ namespace NTest {
             return Base->TxSnapTable(table), *this;
         }
 
-        NTest::TNatural Natural(ui32 table) noexcept
+        NTest::TSchemedCookRow SchemedCookRow(ui32 table) noexcept
         {
             return { RowSchemeFor(table) };
         }
diff --git a/ydb/core/tablet_flat/test/libs/table/test_iter.h b/ydb/core/tablet_flat/test/libs/table/test_iter.h
index f4010ab2b61..c2747256130 100644
--- a/ydb/core/tablet_flat/test/libs/table/test_iter.h
+++ b/ydb/core/tablet_flat/test/libs/table/test_iter.h
@@ -80,7 +80,7 @@ namespace NTest {
         template<typename ...TArgs>
         inline TChecker& IsOpN(ERowOp op, TArgs&&...args)
         {
-            auto row = *TNatural(Scheme).Col(std::forward<TArgs>(args)...);
+            auto row = *TSchemedCookRow(Scheme).Col(std::forward<TArgs>(args)...);
 
             return Is(row, true, op);
         }
@@ -88,7 +88,7 @@ namespace NTest {
         template<typename ...TArgs>
         inline TChecker& HasN(TArgs&&...args)
         {
-            return Has(*TNatural(Scheme).Col(std::forward<TArgs>(args)...));
+            return Has(*TSchemedCookRow(Scheme).Col(std::forward<TArgs>(args)...));
         }
 
         template<typename ...TArgs>
diff --git a/ydb/core/tablet_flat/test/libs/table/test_writer.h b/ydb/core/tablet_flat/test/libs/table/test_writer.h
index 5df2014cd64..704ba0c136e 100644
--- a/ydb/core/tablet_flat/test/libs/table/test_writer.h
+++ b/ydb/core/tablet_flat/test/libs/table/test_writer.h
@@ -285,7 +285,7 @@ namespace NTest {
         template<typename ...TArgs>
         inline TPartCook& AddOpN(ERowOp op, TArgs&&...args)
         {
-            auto row = *TNatural(*Scheme).Col(std::forward<TArgs>(args)...);
+            auto row = *TSchemedCookRow(*Scheme).Col(std::forward<TArgs>(args)...);
 
             return Add(std::move(row), op);
         }
@@ -293,7 +293,7 @@ namespace NTest {
         template<typename ...TArgs>
         inline TPartCook& AddN(TArgs&&...args)
         {
-            auto row = *TNatural(*Scheme).Col(std::forward<TArgs>(args)...);
+            auto row = *TSchemedCookRow(*Scheme).Col(std::forward<TArgs>(args)...);
 
             return Add(std::move(row), ERowOp::Upsert);
         }
diff --git a/ydb/core/tablet_flat/ut/ut_bloom.cpp b/ydb/core/tablet_flat/ut/ut_bloom.cpp
index 0ba3f5b6629..aa4e2118568 100644
--- a/ydb/core/tablet_flat/ut/ut_bloom.cpp
+++ b/ydb/core/tablet_flat/ut/ut_bloom.cpp
@@ -159,18 +159,18 @@ Y_UNIT_TEST_SUITE(Bloom) {
 
         me.To(10).Begin().Apply(*MakeAlter()).Commit();
 
-        const auto ru1 = *me.Natural(1).Col("ba0_huxu", 01234_u64);
-        const auto rw1 = *me.Natural(1).Col("ba2_d7mj", 12340_u64);
-        const auto ru2 = *me.Natural(1).Col("ba4_tfcr", 23401_u64);
-        const auto rw2 = *me.Natural(1).Col("ba6_fdy4", 34012_u64);
-        const auto rw3 = *me.Natural(1).Col("ba8_digr", 40123_u64);
+        const auto ru1 = *me.SchemedCookRow(1).Col("ba0_huxu", 01234_u64);
+        const auto rw1 = *me.SchemedCookRow(1).Col("ba2_d7mj", 12340_u64);
+        const auto ru2 = *me.SchemedCookRow(1).Col("ba4_tfcr", 23401_u64);
+        const auto rw2 = *me.SchemedCookRow(1).Col("ba6_fdy4", 34012_u64);
+        const auto rw3 = *me.SchemedCookRow(1).Col("ba8_digr", 40123_u64);
 
         /* These keys are fitted to be filtered in all parts with
             ByKey Bloom filter enabled, thus in Pw and Pz parts. */
 
-        const auto no1 = *me.Natural(1).Col("ba1_p9lw", 53543_u64);
-        const auto no2 = *me.Natural(1).Col("ba3_g0ny", 53442_u64);
-        const auto no3 = *me.Natural(1).Col("ba5_3hpx", 50894_u64);
+        const auto no1 = *me.SchemedCookRow(1).Col("ba1_p9lw", 53543_u64);
+        const auto no2 = *me.SchemedCookRow(1).Col("ba3_g0ny", 53442_u64);
+        const auto no3 = *me.SchemedCookRow(1).Col("ba5_3hpx", 50894_u64);
 
         /*_ 10: Filter shouldn't be used when it is not enabled, Pu */
 
diff --git a/ydb/core/tablet_flat/ut/ut_charge.cpp b/ydb/core/tablet_flat/ut/ut_charge.cpp
index fa063eb8e73..d9faf3262cf 100644
--- a/ydb/core/tablet_flat/ut/ut_charge.cpp
+++ b/ydb/core/tablet_flat/ut/ut_charge.cpp
@@ -189,9 +189,9 @@ Y_UNIT_TEST_SUITE(Charge) {
             .Col(0, 1,  NScheme::NTypeIds::String)
             .Key({0, 1});
 
-        const auto foo = *TNatural(*lay).Col(555_u32, "foo");
-        const auto bar = *TNatural(*lay).Col(777_u32, "bar");
-        const auto baz = *TNatural(*lay).Col(999_u32, "baz");
+        const auto foo = *TSchemedCookRow(*lay).Col(555_u32, "foo");
+        const auto bar = *TSchemedCookRow(*lay).Col(777_u32, "bar");
+        const auto baz = *TSchemedCookRow(*lay).Col(999_u32, "baz");
 
         NPage::TIndex me(
             TCooker(*lay)
diff --git a/ydb/core/tablet_flat/ut/ut_comp_shard.cpp b/ydb/core/tablet_flat/ut/ut_comp_shard.cpp
index c2dba25ab94..08fc181ba93 100644
--- a/ydb/core/tablet_flat/ut/ut_comp_shard.cpp
+++ b/ydb/core/tablet_flat/ut/ut_comp_shard.cpp
@@ -229,7 +229,7 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
         TRowTool tool(*lay);
         TRowsHeap rows(64 * 1024);
         for (ui64 seq = 0; seq < 4*4; ++seq) {
-            rows.Put(*TNatural(*lay).Col(seq, 500_u32, 42_u32));
+            rows.Put(*TSchemedCookRow(*lay).Col(seq, 500_u32, 42_u32));
         }
 
         auto partView = CreatePart(lay, rows, 4);
@@ -327,7 +327,7 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
         TRowTool tool(*lay);
         TRowsHeap rows(64 * 1024);
         for (ui64 seq = 0; seq < 4*4+2; ++seq) {
-            rows.Put(*TNatural(*lay).Col(seq, 500_u32, 42_u32));
+            rows.Put(*TSchemedCookRow(*lay).Col(seq, 500_u32, 42_u32));
         }
 
         auto partView = CreatePart(lay, rows, 4);
@@ -390,7 +390,7 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
         TRowTool tool(*lay);
         TRowsHeap rows(64 * 1024);
         for (ui64 seq = 0; seq < 10*4+3; ++seq) {
-            rows.Put(*TNatural(*lay).Col(1000 + seq, 42_u32));
+            rows.Put(*TSchemedCookRow(*lay).Col(1000 + seq, 42_u32));
         }
 
         auto partView = CreatePart(lay, rows, 4);
@@ -405,9 +405,9 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
 
         TRowId splitRow = rows.Size() / 2;
         TVector<TSerializedCellVec> splitKeys;
-        splitKeys.emplace_back(TSerializedCellVec::Serialize(tool.KeyCells(*TNatural(*lay).Col(500_u64, 42_u32))));
+        splitKeys.emplace_back(TSerializedCellVec::Serialize(tool.KeyCells(*TSchemedCookRow(*lay).Col(500_u64, 42_u32))));
         splitKeys.emplace_back(TSerializedCellVec::Serialize(tool.KeyCells(rows[splitRow])));
-        splitKeys.emplace_back(TSerializedCellVec::Serialize(tool.KeyCells(*TNatural(*lay).Col(5000_u64, 42_u32))));
+        splitKeys.emplace_back(TSerializedCellVec::Serialize(tool.KeyCells(*TSchemedCookRow(*lay).Col(5000_u64, 42_u32))));
 
         TTableInfo table;
         table.RowScheme = lay.RowScheme();
@@ -467,7 +467,7 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
         TRowTool tool(*lay);
         TRowsHeap rows(64 * 1024);
         for (ui64 seq = 0; seq < rowsPerPage * pageCount; ++seq) {
-            rows.Put(*TNatural(*lay).Col(1000 + seq, 42_u32));
+            rows.Put(*TSchemedCookRow(*lay).Col(1000 + seq, 42_u32));
         }
 
         auto partView = CreatePart(lay, rows, rowsPerPage);
@@ -529,17 +529,17 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
 
         TRowsHeap rows1(64 * 1024);
         for (ui64 seq = 0; seq < 4 * pageCount; ++seq) {
-            rows1.Put(*TNatural(*lay).Col(1000 + seq, 42_u32));
+            rows1.Put(*TSchemedCookRow(*lay).Col(1000 + seq, 42_u32));
         }
 
         TRowsHeap rows2(64 * 1024);
         for (ui64 seq = 0; seq < 2 * pageCount; ++seq) {
-            rows2.Put(*TNatural(*lay).Col(1002 + seq * 2, 42_u32));
+            rows2.Put(*TSchemedCookRow(*lay).Col(1002 + seq * 2, 42_u32));
         }
 
         TRowsHeap rows3(64 * 1024);
         for (ui64 seq = 0; seq < 1 * pageCount; ++seq) {
-            rows3.Put(*TNatural(*lay).Col(1003 + seq * 4, 42_u32));
+            rows3.Put(*TSchemedCookRow(*lay).Col(1003 + seq * 4, 42_u32));
         }
 
         auto partView1 = CreatePart(lay, rows1, 4);
@@ -601,12 +601,12 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
 
         TRowsHeap rows1(64 * 1024);
         for (ui64 seq = 0; seq < 4 * pageCount; ++seq) {
-            rows1.Put(*TNatural(*lay).Col(1000 + seq, 42_u32));
+            rows1.Put(*TSchemedCookRow(*lay).Col(1000 + seq, 42_u32));
         }
 
         TRowsHeap rows2(64 * 1024);
         for (ui64 seq = 0; seq < 2 * pageCount; ++seq) {
-            rows2.Put(*TNatural(*lay).Col(1006 + seq * 2, 42_u32));
+            rows2.Put(*TSchemedCookRow(*lay).Col(1006 + seq * 2, 42_u32));
         }
 
         auto partView1 = CreatePart(lay, rows1, 4);
@@ -668,12 +668,12 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
 
         TRowsHeap rows1(64 * 1024);
         for (ui64 seq = 0; seq < 4 * pageCount; ++seq) {
-            rows1.Put(*TNatural(*lay).Col(1000 + seq, 42_u32));
+            rows1.Put(*TSchemedCookRow(*lay).Col(1000 + seq, 42_u32));
         }
 
         TRowsHeap rows2(64 * 1024);
-        rows2.Put(*TNatural(*lay).Col(1005_u64, 42_u32));
-        rows2.Put(*TNatural(*lay).Col(1006_u64, 42_u32));
+        rows2.Put(*TSchemedCookRow(*lay).Col(1005_u64, 42_u32));
+        rows2.Put(*TSchemedCookRow(*lay).Col(1006_u64, 42_u32));
 
         auto partView1 = CreatePart(lay, rows1, 4);
         auto partView2 = CreatePart(lay, rows2, 4);
@@ -716,12 +716,12 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
 
         TRowsHeap rows1(64 * 1024);
         for (ui64 seq = 0; seq < 4 * pageCount; ++seq) {
-            rows1.Put(*TNatural(*lay).Col(1000 + seq, 42_u32));
+            rows1.Put(*TSchemedCookRow(*lay).Col(1000 + seq, 42_u32));
         }
 
         TRowsHeap rows2(64 * 1024);
         for (ui64 seq = 0; seq < 5; ++seq) {
-            rows2.Put(*TNatural(*lay).Col(1009 + seq, 42_u32));
+            rows2.Put(*TSchemedCookRow(*lay).Col(1009 + seq, 42_u32));
         }
 
         auto partView1 = CreatePart(lay, rows1, 4);
@@ -775,7 +775,7 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
         TRowsHeap rows(64 * 1024);
         TPartCook cook(lay, { false, 4096 });
         for (ui64 seq = 0; seq < rowsCount; ++seq) {
-            rows.Put(*TNatural(*lay).Col(1000 + seq, 42_u32));
+            rows.Put(*TSchemedCookRow(*lay).Col(1000 + seq, 42_u32));
             cook.AddOpN(ERowOp::Erase, 1000 + seq);
         }
 
@@ -838,7 +838,7 @@ Y_UNIT_TEST_SUITE(TShardedCompaction) {
         TRowTool tool(*lay);
         TRowsHeap rows(64 * 1024);
         for (ui64 seq = 0; seq < 4 * pageCount; ++seq) {
-            rows.Put(*TNatural(*lay).Col(1000 + seq, 42_u32));
+            rows.Put(*TSchemedCookRow(*lay).Col(1000 + seq, 42_u32));
         }
 
         auto source = TPartCook(lay, CreateConf(4))
diff --git a/ydb/core/tablet_flat/ut/ut_compaction.cpp b/ydb/core/tablet_flat/ut/ut_compaction.cpp
index ef0d9bbf152..f0fc2cea142 100644
--- a/ydb/core/tablet_flat/ut/ut_compaction.cpp
+++ b/ydb/core/tablet_flat/ut/ut_compaction.cpp
@@ -64,7 +64,7 @@ Y_UNIT_TEST_SUITE(TCompaction) {
             .Col(0, 8,  NScheme::NTypeIds::Uint32, Cimple<ui32>(7))
             .Key({ 0 });
 
-        auto one = *TNatural(*lay).Col<ui64,ui32>(1, 3);
+        auto one = *TSchemedCookRow(*lay).Col<ui64,ui32>(1, 3);
 
         auto eggs =
             TPartCook(lay, { false, 4096 })
diff --git a/ydb/core/tablet_flat/ut/ut_compaction_multi.cpp b/ydb/core/tablet_flat/ut/ut_compaction_multi.cpp
index 6687e80e4a7..beb115c5c02 100644
--- a/ydb/core/tablet_flat/ut/ut_compaction_multi.cpp
+++ b/ydb/core/tablet_flat/ut/ut_compaction_multi.cpp
@@ -185,7 +185,7 @@ Y_UNIT_TEST_SUITE(TCompactionMulti) {
 
         TRowsHeap rows(nrows);
         for (int i = 0; i < nrows; ++i) {
-            rows.Put(*TNatural(*lay).Col(ui64(i), ui64(i * 10)));
+            rows.Put(*TSchemedCookRow(*lay).Col(ui64(i), ui64(i * 10)));
         }
 
         auto initialConf = NPage::TConf{ false, 2044 };
@@ -211,9 +211,9 @@ Y_UNIT_TEST_SUITE(TCompactionMulti) {
         for (int i = 0; i < nrows; ++i) {
             if (i >= nrows-10) {
                 // last 10 rows are strings offloaded to small blobs
-                rows.Put(*TNatural(*lay).Col(ui64(i), TString("Hello, world!")));
+                rows.Put(*TSchemedCookRow(*lay).Col(ui64(i), TString("Hello, world!")));
             } else {
-                rows.Put(*TNatural(*lay).Col(ui64(i), nullptr));
+                rows.Put(*TSchemedCookRow(*lay).Col(ui64(i), nullptr));
             }
         }
 
@@ -241,9 +241,9 @@ Y_UNIT_TEST_SUITE(TCompactionMulti) {
         for (int i = 0; i < nrows; ++i) {
             if (i >= nrows-10) {
                 // last 10 rows are strings offloaded to small blobs
-                rows.Put(*TNatural(*lay).Col(ui64(i), TString("Hello, world!")));
+                rows.Put(*TSchemedCookRow(*lay).Col(ui64(i), TString("Hello, world!")));
             } else {
-                rows.Put(*TNatural(*lay).Col(ui64(i), nullptr));
+                rows.Put(*TSchemedCookRow(*lay).Col(ui64(i), nullptr));
             }
         }
 
diff --git a/ydb/core/tablet_flat/ut/ut_db_iface.cpp b/ydb/core/tablet_flat/ut/ut_db_iface.cpp
index 9843e5a6033..8d508394cf8 100644
--- a/ydb/core/tablet_flat/ut/ut_db_iface.cpp
+++ b/ydb/core/tablet_flat/ut/ut_db_iface.cpp
@@ -31,13 +31,13 @@ Y_UNIT_TEST_SUITE(DBase) {
 
         me.To(10).Begin().Apply(*MakeAlter().Flush()).Commit();
 
-        const auto nil = *me.Natural(1).Col(nullptr);
-        const auto foo = *me.Natural(1).Col("foo", 33_u64);
-        const auto bar = *me.Natural(1).Col("bar", 11_u64);
-        const auto ba1 = *me.Natural(1).Col("bar", ECellOp::Empty, "yo");
-        const auto ba2 = *me.Natural(1).Col("bar", ECellOp::Reset, "me");
-        const auto ba3 = *me.Natural(1).Col("bar", 99_u64, ECellOp::Reset);
-        const auto ba4 = *me.Natural(1).Col("bar", ECellOp::Null, "eh");
+        const auto nil = *me.SchemedCookRow(1).Col(nullptr);
+        const auto foo = *me.SchemedCookRow(1).Col("foo", 33_u64);
+        const auto bar = *me.SchemedCookRow(1).Col("bar", 11_u64);
+        const auto ba1 = *me.SchemedCookRow(1).Col("bar", ECellOp::Empty, "yo");
+        const auto ba2 = *me.SchemedCookRow(1).Col("bar", ECellOp::Reset, "me");
+        const auto ba3 = *me.SchemedCookRow(1).Col("bar", 99_u64, ECellOp::Reset);
+        const auto ba4 = *me.SchemedCookRow(1).Col("bar", ECellOp::Null, "eh");
 
         me.To(11).Iter(1).NoKey(foo).NoKey(bar);
 
@@ -101,11 +101,11 @@ Y_UNIT_TEST_SUITE(DBase) {
 
         me.To(10).Begin().Apply(*MakeAlter().Flush()).Commit();
 
-        const auto bar = *me.Natural(1).Col("bar", 11_u64);
-        const auto ba1 = *me.Natural(1).Col("bar", ECellOp::Empty, "yo");
-        const auto ba2 = *me.Natural(1).Col("bar", ECellOp::Reset, "me");
-        const auto ba3 = *me.Natural(1).Col("bar", 99_u64, ECellOp::Reset);
-        const auto ba4 = *me.Natural(1).Col("bar", ECellOp::Null, "eh");
+        const auto bar = *me.SchemedCookRow(1).Col("bar", 11_u64);
+        const auto ba1 = *me.SchemedCookRow(1).Col("bar", ECellOp::Empty, "yo");
+        const auto ba2 = *me.SchemedCookRow(1).Col("bar", ECellOp::Reset, "me");
+        const auto ba3 = *me.SchemedCookRow(1).Col("bar", 99_u64, ECellOp::Reset);
+        const auto ba4 = *me.SchemedCookRow(1).Col("bar", ECellOp::Null, "eh");
 
         me.To(11).Begin().Add(1, bar).Commit().Select(1).Has(bar);
         me.To(12).Snap(1).Compact(1, false).Select(1).Has(bar);
@@ -138,7 +138,7 @@ Y_UNIT_TEST_SUITE(DBase) {
 
         me.To(10).Begin().Apply(*MakeAlter().Flush());
 
-        const auto nuke = *me.Natural(1).Col(nullptr, 11_u64);
+        const auto nuke = *me.SchemedCookRow(1).Col(nullptr, 11_u64);
 
         me.To(11).Add(1, nuke).Commit().Iter(1).Has(nuke);
 
@@ -151,11 +151,11 @@ Y_UNIT_TEST_SUITE(DBase) {
                 .DropColumn(1, 5)
                 .AddColumnToKey(1, 2));
 
-        const auto foo = *me.Natural(1).Col("foo", nullptr, 33_u64);
-        const auto cap = *me.Natural(1).Col("cap", TOmit{ }, 33_u64);
-        const auto bar = *me.Natural(1).Col("bar", 11_u32, 33_u64, "me", "you");
-        const auto ba8 = *me.Natural(1).Col("bar", 11_u32, 33_u64, "");
-        const auto ba9 = *me.Natural(1).Col("bar", 11_u32, 33_u64, nullptr);
+        const auto foo = *me.SchemedCookRow(1).Col("foo", nullptr, 33_u64);
+        const auto cap = *me.SchemedCookRow(1).Col("cap", TOmit{ }, 33_u64);
+        const auto bar = *me.SchemedCookRow(1).Col("bar", 11_u32, 33_u64, "me", "you");
+        const auto ba8 = *me.SchemedCookRow(1).Col("bar", 11_u32, 33_u64, "");
+        const auto ba9 = *me.SchemedCookRow(1).Col("bar", 11_u32, 33_u64, nullptr);
 
         me.To(13).Put(1, foo, cap, bar).Commit();
         me.Iter(1)
@@ -180,10 +180,10 @@ Y_UNIT_TEST_SUITE(DBase) {
 
         me.To(10).Begin().Apply(*MakeAlter().Flush()).Commit();
 
-        const auto ro1 = *me.Natural(1).Col("row1", 11_u64, "foo");
-        const auto ro2 = *me.Natural(1).Col("row2", 22_u64, "bar");
-        const auto ro3 = *me.Natural(1).Col("row3", 33_u64, "foo");
-        const auto ro4 = *me.Natural(1).Col("row4", 44_u64, "bar");
+        const auto ro1 = *me.SchemedCookRow(1).Col("row1", 11_u64, "foo");
+        const auto ro2 = *me.SchemedCookRow(1).Col("row2", 22_u64, "bar");
+        const auto ro3 = *me.SchemedCookRow(1).Col("row3", 33_u64, "foo");
+        const auto ro4 = *me.SchemedCookRow(1).Col("row4", 44_u64, "bar");
 
         me.Begin().Put(1, ro1, ro2).Commit().Snap(1).Compact(1, false);
         me.Begin().Put(1, ro3, ro4).Commit().Snap(1).Compact(1, false);
@@ -223,10 +223,10 @@ Y_UNIT_TEST_SUITE(DBase) {
 
         me.To(10).Begin().Apply(*MakeAlter().Flush()).Commit();
 
-        const auto ro1 = *me.Natural(1).Col("foo", 11_u64, "boo");
-        const auto ro2 = *me.Natural(1).Col("foo", 22_u64);
-        const auto ro3 = *me.Natural(1).Col("foo");
-        const auto ro4 = *me.Natural(1).Col("foo", 99_u64);
+        const auto ro1 = *me.SchemedCookRow(1).Col("foo", 11_u64, "boo");
+        const auto ro2 = *me.SchemedCookRow(1).Col("foo", 22_u64);
+        const auto ro3 = *me.SchemedCookRow(1).Col("foo");
+        const auto ro4 = *me.SchemedCookRow(1).Col("foo", 99_u64);
 
         /*_ 10: Cut columns from table updating reduced row each time   */
 
@@ -287,7 +287,7 @@ Y_UNIT_TEST_SUITE(DBase) {
 
         me.To(10).Begin().Apply(*MakeAlter(2)).Commit();
 
-        const auto row = *me.Natural(2).Col("foo", 11_u64, "bar");
+        const auto row = *me.SchemedCookRow(2).Col("foo", 11_u64, "bar");
 
         /*_ 10: Basic affects on one table modification */
 
@@ -364,12 +364,12 @@ Y_UNIT_TEST_SUITE(DBase) {
         const TString large42("0123456789abcdef0123456789abcdef0123456789");
         const TString large44("0123456789abcdef0123456789abcdef0123456789ab");
 
-        const auto foo  = *me.Natural(1).Col("foo", 77_u64, "foo");
-        const auto ro30 = *me.Natural(1).Col("l30", 30_u64, large30);
-        const auto ro35 = *me.Natural(1).Col("l35", 35_u64, large35);
-        const auto ro42 = *me.Natural(1).Col("l42", 42_u64, large42);
-        const auto ro44 = *me.Natural(1).Col("l44", 44_u64, large44);
-        const auto zap  = *me.Natural(1).Col("zap", 55_u64, "zap");
+        const auto foo  = *me.SchemedCookRow(1).Col("foo", 77_u64, "foo");
+        const auto ro30 = *me.SchemedCookRow(1).Col("l30", 30_u64, large30);
+        const auto ro35 = *me.SchemedCookRow(1).Col("l35", 35_u64, large35);
+        const auto ro42 = *me.SchemedCookRow(1).Col("l42", 42_u64, large42);
+        const auto ro44 = *me.SchemedCookRow(1).Col("l44", 44_u64, large44);
+        const auto zap  = *me.SchemedCookRow(1).Col("zap", 55_u64, "zap");
 
         /*_ 10: Regular write without producing annex to redo log */
 
@@ -450,9 +450,9 @@ Y_UNIT_TEST_SUITE(DBase) {
         const TString small17("0123456789abcdef0");
         const TString small21("0123456789abcdef01234");
 
-        const auto foo  = *me.Natural(1).Col("foo", 77_u64, "foo");
-        const auto ro17 = *me.Natural(1).Col("s17", 17_u64, small17);
-        const auto ro21 = *me.Natural(1).Col("s21", 21_u64, small21);
+        const auto foo  = *me.SchemedCookRow(1).Col("foo", 77_u64, "foo");
+        const auto ro17 = *me.SchemedCookRow(1).Col("s17", 17_u64, small17);
+        const auto ro21 = *me.SchemedCookRow(1).Col("s21", 21_u64, small21);
 
         /*_ 10: Prepare two parts with attached outer blobs */
 
@@ -494,13 +494,13 @@ Y_UNIT_TEST_SUITE(DBase) {
 
         me.To(10).Begin().Apply(*MakeAlter().Flush()).Commit();
 
-        const auto nil = *me.Natural(1).Col(nullptr);
-        const auto foo = *me.Natural(1).Col("foo", 33_u64);
-        const auto bar = *me.Natural(1).Col("bar", 11_u64);
-        const auto ba1 = *me.Natural(1).Col("bar", ECellOp::Empty, "yo");
-        const auto ba2 = *me.Natural(1).Col("bar", ECellOp::Reset, "me");
-        const auto ba3 = *me.Natural(1).Col("bar", 99_u64, ECellOp::Reset);
-        const auto ba4 = *me.Natural(1).Col("bar", ECellOp::Null, "eh");
+        const auto nil = *me.SchemedCookRow(1).Col(nullptr);
+        const auto foo = *me.SchemedCookRow(1).Col("foo", 33_u64);
+        const auto bar = *me.SchemedCookRow(1).Col("bar", 11_u64);
+        const auto ba1 = *me.SchemedCookRow(1).Col("bar", ECellOp::Empty, "yo");
+        const auto ba2 = *me.SchemedCookRow(1).Col("bar", ECellOp::Reset, "me");
+        const auto ba3 = *me.SchemedCookRow(1).Col("bar", 99_u64, ECellOp::Reset);
+        const auto ba4 = *me.SchemedCookRow(1).Col("bar", ECellOp::Null, "eh");
 
         me.To(11).Iter(1).NoKey(foo).NoKey(bar);
 
@@ -601,17 +601,17 @@ Y_UNIT_TEST_SUITE(DBase) {
         // Add a "null" key with a 0/40 version, for a better code coverage in
         // the version iteration cases, so compaction would actually try
         // descending below 1/50 and won't bail out.
-        me.To(15).Begin().WriteVer({0, 40}).Put(table, *me.Natural(table).Col(nullptr)).Commit();
+        me.To(15).Begin().WriteVer({0, 40}).Put(table, *me.SchemedCookRow(table).Col(nullptr)).Commit();
 
         // Create 1000 rows with 3 consecutive versions each, filling different columns
         me.To(20).Begin();
         for (ui64 i = 1000; i < 2000; ++i) {
             // Version 1/50, keys added, but all columns are empty (default)
-            me.WriteVer({1, 50}).Put(table, *me.Natural(table).Col(i, ECellOp::Empty, ECellOp::Empty));
+            me.WriteVer({1, 50}).Put(table, *me.SchemedCookRow(table).Col(i, ECellOp::Empty, ECellOp::Empty));
             // Version 2/60, keys updated with arg1=i
-            me.WriteVer({2, 60}).Put(table, *me.Natural(table).Col(i, i, ECellOp::Empty));
+            me.WriteVer({2, 60}).Put(table, *me.SchemedCookRow(table).Col(i, i, ECellOp::Empty));
             // Version 3/70, keys updated with arg2=3000-i
-            me.WriteVer({3, 70}).Put(table, *me.Natural(table).Col(i, ECellOp::Empty, 3000-i));
+            me.WriteVer({3, 70}).Put(table, *me.SchemedCookRow(table).Col(i, ECellOp::Empty, 3000-i));
         }
         me.Commit().Snap(table);
         if (compactMemTables) {
@@ -621,7 +621,7 @@ Y_UNIT_TEST_SUITE(DBase) {
         // Create 1000 more rows using different memtables
         me.To(22).Begin();
         for (ui64 i = 2000; i < 3000; ++i) {
-            me.WriteVer({1, 50}).Put(table, *me.Natural(table).Col(i, ECellOp::Empty, ECellOp::Empty));
+            me.WriteVer({1, 50}).Put(table, *me.SchemedCookRow(table).Col(i, ECellOp::Empty, ECellOp::Empty));
         }
         me.Commit().Snap(table);
         if (compactMemTables) {
@@ -630,7 +630,7 @@ Y_UNIT_TEST_SUITE(DBase) {
 
         me.To(23).Begin();
         for (ui64 i = 2000; i < 3000; ++i) {
-            me.WriteVer({2, 60}).Put(table, *me.Natural(table).Col(i, i, ECellOp::Empty));
+            me.WriteVer({2, 60}).Put(table, *me.SchemedCookRow(table).Col(i, i, ECellOp::Empty));
         }
         me.Commit().Snap(table);
         if (compactMemTables) {
@@ -639,7 +639,7 @@ Y_UNIT_TEST_SUITE(DBase) {
 
         me.To(24).Begin();
         for (ui64 i = 2000; i < 3000; ++i) {
-            me.WriteVer({3, 70}).Put(table, *me.Natural(table).Col(i, ECellOp::Empty, 3000-i));
+            me.WriteVer({3, 70}).Put(table, *me.SchemedCookRow(table).Col(i, ECellOp::Empty, 3000-i));
         }
         me.Commit().Snap(table);
         if (compactMemTables) {
@@ -655,8 +655,8 @@ Y_UNIT_TEST_SUITE(DBase) {
         me.To(30);
         for (ui64 i = 1000; i < 3000; ++i) {
             // No key before 1/50
-            me.ReadVer({1, 49}).Select(table).NoKey(*me.Natural(table).Col(i));
-            me.ReadVer({1, 49}).Iter(table).NoKey(*me.Natural(table).Col(i));
+            me.ReadVer({1, 49}).Select(table).NoKey(*me.SchemedCookRow(table).Col(i));
+            me.ReadVer({1, 49}).Iter(table).NoKey(*me.SchemedCookRow(table).Col(i));
             // Key with default values until 2/60
             me.ReadVer({2, 59}).Select(table).HasN(i, 10004_u64, 10005_u64);
             me.ReadVer({2, 59}).Iter(table).HasN(i, 10004_u64, 10005_u64);
@@ -674,15 +674,15 @@ Y_UNIT_TEST_SUITE(DBase) {
 
         // Verify iteration before 1/50
         me.To(32).ReadVer({1, 49}).Iter(table, false)
-            .Seek({ }, ESeek::Lower).Is(*me.Natural(table).Col(nullptr, 10004_u64, 10005_u64))
+            .Seek({ }, ESeek::Lower).Is(*me.SchemedCookRow(table).Col(nullptr, 10004_u64, 10005_u64))
             .Next().Is(EReady::Gone);
 
         // Verify iteration before 2/60
         {
             auto checker = me.To(33).ReadVer({2, 59}).Iter(table, false)
-                .Seek({ }, ESeek::Lower).Is(*me.Natural(table).Col(nullptr, 10004_u64, 10005_u64));
+                .Seek({ }, ESeek::Lower).Is(*me.SchemedCookRow(table).Col(nullptr, 10004_u64, 10005_u64));
             for (ui64 i = 1000; i < 3000; ++i) {
-                checker.Next().Is(*me.Natural(table).Col(i, 10004_u64, 10005_u64));
+                checker.Next().Is(*me.SchemedCookRow(table).Col(i, 10004_u64, 10005_u64));
             }
             checker.Next().Is(EReady::Gone);
         }
@@ -690,9 +690,9 @@ Y_UNIT_TEST_SUITE(DBase) {
         // Verify iteration before 3/70
         {
             auto checker = me.To(34).ReadVer({3, 69}).Iter(table, false)
-                .Seek({ }, ESeek::Lower).Is(*me.Natural(table).Col(nullptr, 10004_u64, 10005_u64));
+                .Seek({ }, ESeek::Lower).Is(*me.SchemedCookRow(table).Col(nullptr, 10004_u64, 10005_u64));
             for (ui64 i = 1000; i < 3000; ++i) {
-                checker.Next().Is(*me.Natural(table).Col(i, i, 10005_u64));
+                checker.Next().Is(*me.SchemedCookRow(table).Col(i, i, 10005_u64));
             }
             checker.Next().Is(EReady::Gone);
         }
@@ -700,9 +700,9 @@ Y_UNIT_TEST_SUITE(DBase) {
         // Verify iteration at 3/70
         {
             auto checker = me.To(35).ReadVer({3, 70}).Iter(table, false)
-                .Seek({ }, ESeek::Lower).Is(*me.Natural(table).Col(nullptr, 10004_u64, 10005_u64));
+                .Seek({ }, ESeek::Lower).Is(*me.SchemedCookRow(table).Col(nullptr, 10004_u64, 10005_u64));
             for (ui64 i = 1000; i < 3000; ++i) {
-                checker.Next().Is(*me.Natural(table).Col(i, i, 3000-i));
+                checker.Next().Is(*me.SchemedCookRow(table).Col(i, i, 3000-i));
             }
             checker.Next().Is(EReady::Gone);
         }
@@ -710,9 +710,9 @@ Y_UNIT_TEST_SUITE(DBase) {
         // Verify iteration at HEAD
         {
             auto checker = me.To(36).ReadVer(TRowVersion::Max()).Iter(table, false)
-                .Seek({ }, ESeek::Lower).Is(*me.Natural(table).Col(nullptr, 10004_u64, 10005_u64));
+                .Seek({ }, ESeek::Lower).Is(*me.SchemedCookRow(table).Col(nullptr, 10004_u64, 10005_u64));
             for (ui64 i = 1000; i < 3000; ++i) {
-                checker.Next().Is(*me.Natural(table).Col(i, i, 3000-i));
+                checker.Next().Is(*me.SchemedCookRow(table).Col(i, i, 3000-i));
             }
             checker.Next().Is(EReady::Gone);
         }
diff --git a/ydb/core/tablet_flat/ut/ut_memtable.cpp b/ydb/core/tablet_flat/ut/ut_memtable.cpp
index d5b6c328648..ed0e0bddccd 100644
--- a/ydb/core/tablet_flat/ut/ut_memtable.cpp
+++ b/ydb/core/tablet_flat/ut/ut_memtable.cpp
@@ -40,14 +40,14 @@ Y_UNIT_TEST_SUITE(Memtable)
 
         /* Test copied from TPart::Basics with except of iteration */
 
-        const auto foo = *TNatural(*lay).Col(555_u32, "foo", 3.14, nullptr);
-        const auto bar = *TNatural(*lay).Col(777_u32, "bar", 2.72, true);
+        const auto foo = *TSchemedCookRow(*lay).Col(555_u32, "foo", 3.14, nullptr);
+        const auto bar = *TSchemedCookRow(*lay).Col(777_u32, "bar", 2.72, true);
 
         TCheckIt wrap(TCooker(lay).Add(foo).Add(bar).Unwrap(), { });
 
         wrap.To(10).Has(foo).Has(bar);
-        wrap.To(11).NoVal(*TNatural(*lay).Col(555_u32, "foo", 10.));
-        wrap.To(12).NoKey(*TNatural(*lay).Col(888_u32, "foo", 3.14));
+        wrap.To(11).NoVal(*TSchemedCookRow(*lay).Col(555_u32, "foo", 10.));
+        wrap.To(12).NoKey(*TSchemedCookRow(*lay).Col(888_u32, "foo", 3.14));
 
         /*_ Basic lower and upper bounds lookup semantic  */
 
@@ -64,8 +64,8 @@ Y_UNIT_TEST_SUITE(Memtable)
         /* ... but incomplete keys are padded with +inf instead of nulls
             on lookup. Check that it really happens for Seek()'s */
 
-        wrap.To(33).Seek(*TNatural(*lay).Col(555_u32), ESeek::Lower).Is(bar);
-        wrap.To(34).Seek(*TNatural(*lay).Col(555_u32), ESeek::Upper).Is(bar);
+        wrap.To(33).Seek(*TSchemedCookRow(*lay).Col(555_u32), ESeek::Lower).Is(bar);
+        wrap.To(34).Seek(*TSchemedCookRow(*lay).Col(555_u32), ESeek::Upper).Is(bar);
 
         /*_ Basic iteration over two rows in tables */
 
@@ -79,14 +79,14 @@ Y_UNIT_TEST_SUITE(Memtable)
 
         /* Test copied from TPart::Basics with except of iteration */
 
-        const auto foo = *TNatural(*lay).Col(555_u32, "foo", 3.14, nullptr);
-        const auto bar = *TNatural(*lay).Col(777_u32, "bar", 2.72, true);
+        const auto foo = *TSchemedCookRow(*lay).Col(555_u32, "foo", 3.14, nullptr);
+        const auto bar = *TSchemedCookRow(*lay).Col(777_u32, "bar", 2.72, true);
 
         TCheckReverseIt wrap(TCooker(lay).Add(foo).Add(bar).Unwrap(), { });
 
         wrap.To(10).Has(foo).Has(bar);
-        wrap.To(11).NoVal(*TNatural(*lay).Col(555_u32, "foo", 10.));
-        wrap.To(12).NoKey(*TNatural(*lay).Col(888_u32, "foo", 3.14));
+        wrap.To(11).NoVal(*TSchemedCookRow(*lay).Col(555_u32, "foo", 10.));
+        wrap.To(12).NoKey(*TSchemedCookRow(*lay).Col(888_u32, "foo", 3.14));
 
         /*_ Basic lower and upper bounds lookup semantic  */
 
@@ -104,8 +104,8 @@ Y_UNIT_TEST_SUITE(Memtable)
         /* ... but incomplete keys are padded with +inf instead of nulls
             on lookup. Check that it really happens for Seek()'s */
 
-        wrap.To(33).Seek(*TNatural(*lay).Col(555_u32), ESeek::Lower).Is(foo);
-        wrap.To(34).Seek(*TNatural(*lay).Col(555_u32), ESeek::Upper).Is(foo);
+        wrap.To(33).Seek(*TSchemedCookRow(*lay).Col(555_u32), ESeek::Lower).Is(foo);
+        wrap.To(34).Seek(*TSchemedCookRow(*lay).Col(555_u32), ESeek::Upper).Is(foo);
 
         /*_ Basic iteration over two rows in tables */
 
@@ -117,8 +117,8 @@ Y_UNIT_TEST_SUITE(Memtable)
     {
         const auto lay = BasicRowLayout();
 
-        auto reset = *TNatural(*lay).Col(555_u32, "foo", ECellOp::Reset);
-        auto null  = *TNatural(*lay).Col(556_u32, "foo", ECellOp::Null);
+        auto reset = *TSchemedCookRow(*lay).Col(555_u32, "foo", ECellOp::Reset);
+        auto null  = *TSchemedCookRow(*lay).Col(556_u32, "foo", ECellOp::Null);
 
         TCooker cooker(lay);
 
@@ -130,13 +130,13 @@ Y_UNIT_TEST_SUITE(Memtable)
     {
         const auto lay = BasicRowLayout();
 
-        auto r0W = *TNatural(*lay).Col(555_u32, "foo", 3.14, nullptr);
-        auto r1W = *TNatural(*lay).Col(555_u32, "foo", nullptr, false);
-        auto r2W = *TNatural(*lay).Col(555_u32, "foo", 2.72);
-        auto r2R = *TNatural(*lay).Col(555_u32, "foo", 2.72, false);
-        auto r3W = *TNatural(*lay).Col(555_u32, "foo", nullptr, true);
-        auto r4W = *TNatural(*lay).Col(555_u32, "foo", ECellOp::Reset);
-        auto r4R = *TNatural(*lay).Col(555_u32, "foo", 3.14, true);
+        auto r0W = *TSchemedCookRow(*lay).Col(555_u32, "foo", 3.14, nullptr);
+        auto r1W = *TSchemedCookRow(*lay).Col(555_u32, "foo", nullptr, false);
+        auto r2W = *TSchemedCookRow(*lay).Col(555_u32, "foo", 2.72);
+        auto r2R = *TSchemedCookRow(*lay).Col(555_u32, "foo", 2.72, false);
+        auto r3W = *TSchemedCookRow(*lay).Col(555_u32, "foo", nullptr, true);
+        auto r4W = *TSchemedCookRow(*lay).Col(555_u32, "foo", ECellOp::Reset);
+        auto r4R = *TSchemedCookRow(*lay).Col(555_u32, "foo", 3.14, true);
 
         TCooker cooker(lay);
 
diff --git a/ydb/core/tablet_flat/ut/ut_other.cpp b/ydb/core/tablet_flat/ut/ut_other.cpp
index ea1c287283e..9cb6ca02c54 100644
--- a/ydb/core/tablet_flat/ut/ut_other.cpp
+++ b/ydb/core/tablet_flat/ut/ut_other.cpp
@@ -14,7 +14,7 @@ Y_UNIT_TEST_SUITE(NOther) {
     {
         NWriter::TConf conf;
 
-        conf.Groups[0].Block = 128;       /* Page collection blob size */
+        conf.Groups[0].MaxBlobSize = 128;       /* Page collection blob size */
         conf.Slots = { { 1, 11 }, { 3, 13 }, { 5, 17 } };
         conf.Groups[0].Channel = 3;     /* Put data to channel 3 grp 13 */
         conf.BlobsChannel = 5;    /* Put blobs to channel 5 grp 17 */
diff --git a/ydb/core/tablet_flat/ut/ut_pages.cpp b/ydb/core/tablet_flat/ut/ut_pages.cpp
index abe9e719057..4328c0ea9fd 100644
--- a/ydb/core/tablet_flat/ut/ut_pages.cpp
+++ b/ydb/core/tablet_flat/ut/ut_pages.cpp
@@ -35,8 +35,8 @@ Y_UNIT_TEST_SUITE(NPage) {
             .Col(0, 1,  NScheme::NTypeIds::String)
             .Key({ 0 });
 
-        const auto foo = *TNatural(*lay).Col(555_u32, "foo");
-        const auto bar = *TNatural(*lay).Col(777_u32, "bar");
+        const TRow foo = *TSchemedCookRow(*lay).Col(555_u32, "foo");
+        const TRow bar = *TSchemedCookRow(*lay).Col(777_u32, "bar");
 
         NPage::TConf conf{ true, 2 * 1024 };
 
diff --git a/ydb/core/tablet_flat/ut/ut_part.cpp b/ydb/core/tablet_flat/ut/ut_part.cpp
index e046b861d26..e9cdf756b58 100644
--- a/ydb/core/tablet_flat/ut/ut_part.cpp
+++ b/ydb/core/tablet_flat/ut/ut_part.cpp
@@ -101,14 +101,14 @@ Y_UNIT_TEST_SUITE(TPart) {
             .Col(0, 3,  NScheme::NTypeIds::Bool)
             .Key({0, 1});
 
-        const auto foo = *TNatural(*lay).Col(555_u32, "foo", 3.14, nullptr);
-        const auto bar = *TNatural(*lay).Col(777_u32, "bar", 2.72, true);
+        const auto foo = *TSchemedCookRow(*lay).Col(555_u32, "foo", 3.14, nullptr);
+        const auto bar = *TSchemedCookRow(*lay).Col(777_u32, "bar", 2.72, true);
 
         TCheckIt wrap(TPartCook(lay, { }).Add(foo).Add(bar).Finish(), { });
 
         wrap.To(10).Has(foo).Has(bar);
-        wrap.To(11).NoVal(*TNatural(*lay).Col(555_u32, "foo", 10.));
-        wrap.To(12).NoKey(*TNatural(*lay).Col(888_u32, "foo", 3.14));
+        wrap.To(11).NoVal(*TSchemedCookRow(*lay).Col(555_u32, "foo", 10.));
+        wrap.To(12).NoKey(*TSchemedCookRow(*lay).Col(888_u32, "foo", 3.14));
 
         /*_ Basic lower and upper bounds lookup semantic  */
 
@@ -125,8 +125,8 @@ Y_UNIT_TEST_SUITE(TPart) {
         /* ... but incomplete keys are padded with +inf instead of nulls
             on lookup. Check that it really happens for Seek()'s */
 
-        wrap.To(33).Seek(*TNatural(*lay).Col(555_u32), ESeek::Lower).Is(bar);
-        wrap.To(34).Seek(*TNatural(*lay).Col(555_u32), ESeek::Upper).Is(bar);
+        wrap.To(33).Seek(*TSchemedCookRow(*lay).Col(555_u32), ESeek::Lower).Is(bar);
+        wrap.To(34).Seek(*TSchemedCookRow(*lay).Col(555_u32), ESeek::Upper).Is(bar);
 
         /* Verify part has correct first and last key in the index */
 
@@ -152,8 +152,8 @@ Y_UNIT_TEST_SUITE(TPart) {
             .Col(2, 3, NScheme::NTypeIds::Bool)
             .Key({ 0 });
 
-        const auto foo = *TNatural(*lay).Col(555_u32, "foo", 3.14, nullptr);
-        const auto bar = *TNatural(*lay).Col(777_u32, "bar", 2.72, true);
+        const auto foo = *TSchemedCookRow(*lay).Col(555_u32, "foo", 3.14, nullptr);
+        const auto bar = *TSchemedCookRow(*lay).Col(777_u32, "bar", 2.72, true);
 
         auto eggs = TPartCook(lay, PageConf(/* groups = */ 3)).Add(foo).Add(bar).Finish();
         auto part = eggs.Lone();
@@ -193,14 +193,14 @@ Y_UNIT_TEST_SUITE(TPart) {
 
         TCheckIt wrap(std::move(eggs), { });
 
-        auto trA = *TNatural(*fake).Col(10_u64, 3_u32, 7_u32, 77_u32);
-        auto trB = *TNatural(*fake).Col(12_u64, 3_u32, 7_u32, 44_u32);
-        auto trC = *TNatural(*fake).Col(17_u64, 3_u32, 7_u32, nullptr);
-        auto trD = *TNatural(*fake).Col(19_u64, 3_u32, 7_u32, 99_u32);
+        auto trA = *TSchemedCookRow(*fake).Col(10_u64, 3_u32, 7_u32, 77_u32);
+        auto trB = *TSchemedCookRow(*fake).Col(12_u64, 3_u32, 7_u32, 44_u32);
+        auto trC = *TSchemedCookRow(*fake).Col(17_u64, 3_u32, 7_u32, nullptr);
+        auto trD = *TSchemedCookRow(*fake).Col(19_u64, 3_u32, 7_u32, 99_u32);
 
-        auto low = *TNatural(*fake).Col(10_u64, 2_u32, 2_u32);
-        auto mid = *TNatural(*fake).Col(10_u64, 3_u32, 5_u32);
-        auto upp = *TNatural(*fake).Col(10_u64, 3_u32, 8_u32);
+        auto low = *TSchemedCookRow(*fake).Col(10_u64, 2_u32, 2_u32);
+        auto mid = *TSchemedCookRow(*fake).Col(10_u64, 3_u32, 5_u32);
+        auto upp = *TSchemedCookRow(*fake).Col(10_u64, 3_u32, 8_u32);
 
         wrap.To(10).Has(trA);   /* default values in key    */
         wrap.To(11).Has(trB);   /* default values in key    */
@@ -224,7 +224,7 @@ Y_UNIT_TEST_SUITE(TPart) {
 
         lay.Col(0, 0, ETypes::Uint32).Col(0, 1, ETypes::String).Key({ 0 });
 
-        const auto foo = *TNatural(*lay).Col(7_u32, TString(128, 'x'));
+        const auto foo = *TSchemedCookRow(*lay).Col(7_u32, TString(128, 'x'));
 
         TCheckIt wrap(TPartCook(lay, { true, 99, 32 }).Add(foo).Finish(), { });
 
@@ -262,7 +262,7 @@ Y_UNIT_TEST_SUITE(TPart) {
         { /*_ Check marker of absent external blob in TCell */
             wrap.Displace<IPages>(new TNoEnv{ true, ELargeObjNeed::No });
 
-            auto marked = *TNatural(*lay).Col(7_u32, glob);
+            auto marked = *TSchemedCookRow(*lay).Col(7_u32, glob);
 
             wrap.To(16).Seek(foo, ESeek::Exact).Is(marked);
         }
@@ -279,7 +279,7 @@ Y_UNIT_TEST_SUITE(TPart) {
         TPartCook cook(lay, { });
 
         const auto glob = cook.PutBlob(TString(128, 'x'), 0);
-        const auto foo = *TNatural(*lay).Col(7_u32,  glob);
+        const auto foo = *TSchemedCookRow(*lay).Col(7_u32,  glob);
 
         TCheckIt wrap(cook.Add(foo).Finish(), { });
 
@@ -307,8 +307,8 @@ Y_UNIT_TEST_SUITE(TPart) {
 
         TPartCook cook(lay, PageConf());
 
-        const auto foo = *TNatural(*lay).Col(7_u32, TString(24, 'x'));
-        const auto bar = *TNatural(*lay).Col(8_u32, TString(10, 'x'));
+        const auto foo = *TSchemedCookRow(*lay).Col(7_u32, TString(24, 'x'));
+        const auto bar = *TSchemedCookRow(*lay).Col(8_u32, TString(10, 'x'));
 
         TCheckIt wrap(cook.Add(foo).Add(bar).Finish(), { });
 
@@ -432,13 +432,13 @@ Y_UNIT_TEST_SUITE(TPart) {
             .Col(2, 3, NScheme::NTypeIds::Bool)
             .Key({ 0 });
 
-        const auto hey = *TNatural(*lay).Col(333_u32, "hey", 0.25, true);
-        const auto foo = *TNatural(*lay).Col(555_u32);
-        const auto foo1 = *TNatural(*lay).Col(555_u32, "foo1", 3.14, nullptr);
-        const auto foo2 = *TNatural(*lay).Col(555_u32, "foo2", 4.25, false);
-        const auto foo3 = *TNatural(*lay).Col(555_u32, "foo3", 7.75, true);
-        const auto bar = *TNatural(*lay).Col(777_u32, "bar", 2.72, true);
-        const auto baz = *TNatural(*lay).Col(999_u32, "baz", 0.0, false);
+        const auto hey = *TSchemedCookRow(*lay).Col(333_u32, "hey", 0.25, true);
+        const auto foo = *TSchemedCookRow(*lay).Col(555_u32);
+        const auto foo1 = *TSchemedCookRow(*lay).Col(555_u32, "foo1", 3.14, nullptr);
+        const auto foo2 = *TSchemedCookRow(*lay).Col(555_u32, "foo2", 4.25, false);
+        const auto foo3 = *TSchemedCookRow(*lay).Col(555_u32, "foo3", 7.75, true);
+        const auto bar = *TSchemedCookRow(*lay).Col(777_u32, "bar", 2.72, true);
+        const auto baz = *TSchemedCookRow(*lay).Col(999_u32, "baz", 0.0, false);
 
         auto conf = PageConf(/* groups = */ 3);
         conf.MinRowVersion = TRowVersion(0, 50);
@@ -516,8 +516,8 @@ Y_UNIT_TEST_SUITE(TPart) {
             .Col(2, 3, NScheme::NTypeIds::Bool)
             .Key({ 0 });
 
-        const auto foo = *TNatural(*lay).Col(555_u32);
-        const auto bar = *TNatural(*lay).Col(777_u32);
+        const auto foo = *TSchemedCookRow(*lay).Col(555_u32);
+        const auto bar = *TSchemedCookRow(*lay).Col(777_u32);
 
         auto conf = PageConf(/* groups = */ 3);
         auto cook = TPartCook(lay, conf);
@@ -527,7 +527,7 @@ Y_UNIT_TEST_SUITE(TPart) {
         for (int i = 0; i <= 1000; ++i) {
             TString s = TStringBuilder() << "foo_xxxxxxxxxxxxxxxx" << i;
             foov.emplace_back(1, 1000-i);
-            foos.emplace_back(*TNatural(*lay).Col(555_u32, s.c_str(), i * 0.1, nullptr));
+            foos.emplace_back(*TSchemedCookRow(*lay).Col(555_u32, s.c_str(), i * 0.1, nullptr));
             cook.Ver(foov.back()).Add(foos.back());
         }
 
@@ -536,12 +536,12 @@ Y_UNIT_TEST_SUITE(TPart) {
         for (int i = 0; i <= 1000; ++i) {
             TString s = TStringBuilder() << "bar_xxxxxxxxxxxxxxxx" << i;
             barv.emplace_back(2, 1000-i);
-            bars.emplace_back(*TNatural(*lay).Col(777_u32, s.c_str(), i * 0.2, i % 2 == 0));
+            bars.emplace_back(*TSchemedCookRow(*lay).Col(777_u32, s.c_str(), i * 0.2, i % 2 == 0));
             cook.Ver(barv.back()).Add(bars.back());
         }
 
         // This row lowers min version, so we can trigger necessary search paths
-        const auto baz = *TNatural(*lay).Col(999_u32, "baz", 0.42, true);
+        const auto baz = *TSchemedCookRow(*lay).Col(999_u32, "baz", 0.42, true);
         cook.Ver({0, 42}).Add(baz);
 
         auto eggs = cook.Finish();
@@ -583,8 +583,8 @@ Y_UNIT_TEST_SUITE(TPart) {
         auto conf = PageConf();
         auto cook = TPartCook(lay, conf);
 
-        const auto foo = *TNatural(*lay).Col(555_u32);
-        const auto bar = *TNatural(*lay).Col(777_u32);
+        const auto foo = *TSchemedCookRow(*lay).Col(555_u32);
+        const auto bar = *TSchemedCookRow(*lay).Col(777_u32);
 
         for (int i = 1; i <= 1000; ++i) {
             TTag tag = 1 + (i - 1) % 3;
diff --git a/ydb/core/tablet_flat/ut/ut_part_multi.cpp b/ydb/core/tablet_flat/ut/ut_part_multi.cpp
index cdc6714a55f..9167ed5b04a 100644
--- a/ydb/core/tablet_flat/ut/ut_part_multi.cpp
+++ b/ydb/core/tablet_flat/ut/ut_part_multi.cpp
@@ -26,10 +26,10 @@ Y_UNIT_TEST_SUITE(TPartMulti) {
             .Col(0, 3,  NScheme::NTypeIds::Bool)
             .Key({0, 1});
 
-        const auto foo = *TNatural(*lay).Col(555_u32, "foo", 3.14, nullptr);
-        const auto bar = *TNatural(*lay).Col(777_u32, "bar", 2.72, true);
-        const auto baz = *TNatural(*lay).Col(888_u32, "baz", 5.42, false);
-        const auto zzz = *TNatural(*lay).Col(999_u32, "zzz", 4.11, false);
+        const auto foo = *TSchemedCookRow(*lay).Col(555_u32, "foo", 3.14, nullptr);
+        const auto bar = *TSchemedCookRow(*lay).Col(777_u32, "bar", 2.72, true);
+        const auto baz = *TSchemedCookRow(*lay).Col(888_u32, "baz", 5.42, false);
+        const auto zzz = *TSchemedCookRow(*lay).Col(999_u32, "zzz", 4.11, false);
 
         NTest::TPartEggs eggs = {
             nullptr,
@@ -43,8 +43,8 @@ Y_UNIT_TEST_SUITE(TPartMulti) {
         TCheckIt wrap(eggs, { });
 
         wrap.To(10).Has(foo).Has(bar);
-        wrap.To(11).NoVal(*TNatural(*lay).Col(555_u32, "foo", 10.));
-        wrap.To(12).NoKey(*TNatural(*lay).Col(888_u32, "foo", 3.14));
+        wrap.To(11).NoVal(*TSchemedCookRow(*lay).Col(555_u32, "foo", 10.));
+        wrap.To(12).NoKey(*TSchemedCookRow(*lay).Col(888_u32, "foo", 3.14));
 
         /*_ Basic lower and upper bounds lookup semantic  */
 
@@ -66,21 +66,21 @@ Y_UNIT_TEST_SUITE(TPartMulti) {
         /* ... but incomplete keys are padded with +inf instead of nulls
             on lookup. Check that it really happens for Seek()'s */
 
-        wrap.To(33).Seek(*TNatural(*lay).Col(555_u32), ESeek::Lower).Is(bar);
-        wrap.To(34).Seek(*TNatural(*lay).Col(555_u32), ESeek::Upper).Is(bar);
-        wrap.To(35).Seek(*TNatural(*lay).Col(777_u32), ESeek::Lower).Is(baz);
-        wrap.To(36).Seek(*TNatural(*lay).Col(777_u32), ESeek::Upper).Is(baz);
+        wrap.To(33).Seek(*TSchemedCookRow(*lay).Col(555_u32), ESeek::Lower).Is(bar);
+        wrap.To(34).Seek(*TSchemedCookRow(*lay).Col(555_u32), ESeek::Upper).Is(bar);
+        wrap.To(35).Seek(*TSchemedCookRow(*lay).Col(777_u32), ESeek::Lower).Is(baz);
+        wrap.To(36).Seek(*TSchemedCookRow(*lay).Col(777_u32), ESeek::Upper).Is(baz);
 
         /*_ Next should move to the next part correctly */
 
-        wrap.To(40).Seek(*TNatural(*lay).Col(777_u32, "aaa"), ESeek::Lower).Is(bar)
+        wrap.To(40).Seek(*TSchemedCookRow(*lay).Col(777_u32, "aaa"), ESeek::Lower).Is(bar)
             .To(41).Next().Is(baz)
             .To(42).Next().Is(zzz)
             .To(43).Next().Is(EReady::Gone);
 
         /*_ Next must not be confused by a failed exact seek */
 
-        wrap.To(50).Seek(*TNatural(*lay).Col(777_u32, "aaa"), ESeek::Exact).Is(EReady::Gone)
+        wrap.To(50).Seek(*TSchemedCookRow(*lay).Col(777_u32, "aaa"), ESeek::Exact).Is(EReady::Gone)
             .To(51).Next().Is(EReady::Gone);
     }
 
@@ -95,10 +95,10 @@ Y_UNIT_TEST_SUITE(TPartMulti) {
             .Col(0, 3,  NScheme::NTypeIds::Bool)
             .Key({0, 1});
 
-        const auto foo = *TNatural(*lay).Col(555_u32, "foo", 3.14, nullptr);
-        const auto bar = *TNatural(*lay).Col(777_u32, "bar", 2.72, true);
-        const auto baz = *TNatural(*lay).Col(888_u32, "baz", 5.42, false);
-        const auto zzz = *TNatural(*lay).Col(999_u32, "zzz", 4.11, false);
+        const auto foo = *TSchemedCookRow(*lay).Col(555_u32, "foo", 3.14, nullptr);
+        const auto bar = *TSchemedCookRow(*lay).Col(777_u32, "bar", 2.72, true);
+        const auto baz = *TSchemedCookRow(*lay).Col(888_u32, "baz", 5.42, false);
+        const auto zzz = *TSchemedCookRow(*lay).Col(999_u32, "zzz", 4.11, false);
 
         NTest::TPartEggs eggs = {
             nullptr,
@@ -112,8 +112,8 @@ Y_UNIT_TEST_SUITE(TPartMulti) {
         TCheckReverseIt wrap(eggs, { });
 
         wrap.To(10).Has(foo).Has(bar);
-        wrap.To(11).NoVal(*TNatural(*lay).Col(555_u32, "foo", 10.));
-        wrap.To(12).NoKey(*TNatural(*lay).Col(888_u32, "foo", 3.14));
+        wrap.To(11).NoVal(*TSchemedCookRow(*lay).Col(555_u32, "foo", 10.));
+        wrap.To(12).NoKey(*TSchemedCookRow(*lay).Col(888_u32, "foo", 3.14));
 
         /*_ Basic lower and upper bounds lookup semantic  */
 
@@ -135,21 +135,21 @@ Y_UNIT_TEST_SUITE(TPartMulti) {
         /* ... but incomplete keys are padded with +inf instead of nulls
             on lookup. Check that it really happens for Seek()'s */
 
-        wrap.To(33).Seek(*TNatural(*lay).Col(555_u32), ESeek::Lower).Is(foo);
-        wrap.To(34).Seek(*TNatural(*lay).Col(555_u32), ESeek::Upper).Is(foo);
-        wrap.To(35).Seek(*TNatural(*lay).Col(777_u32), ESeek::Lower).Is(bar);
-        wrap.To(36).Seek(*TNatural(*lay).Col(777_u32), ESeek::Upper).Is(bar);
+        wrap.To(33).Seek(*TSchemedCookRow(*lay).Col(555_u32), ESeek::Lower).Is(foo);
+        wrap.To(34).Seek(*TSchemedCookRow(*lay).Col(555_u32), ESeek::Upper).Is(foo);
+        wrap.To(35).Seek(*TSchemedCookRow(*lay).Col(777_u32), ESeek::Lower).Is(bar);
+        wrap.To(36).Seek(*TSchemedCookRow(*lay).Col(777_u32), ESeek::Upper).Is(bar);
 
         /*_ Prev should move to the previous part correctly */
 
-        wrap.To(40).Seek(*TNatural(*lay).Col(999_u32, "aaa"), ESeek::Lower).Is(baz)
+        wrap.To(40).Seek(*TSchemedCookRow(*lay).Col(999_u32, "aaa"), ESeek::Lower).Is(baz)
             .To(41).Next().Is(bar)
             .To(42).Next().Is(foo)
             .To(43).Next().Is(EReady::Gone);
 
         /*_ Prev must not be confused by a failed exact seek */
 
-        wrap.To(50).Seek(*TNatural(*lay).Col(777_u32, "aaa"), ESeek::Exact).Is(EReady::Gone)
+        wrap.To(50).Seek(*TSchemedCookRow(*lay).Col(777_u32, "aaa"), ESeek::Exact).Is(EReady::Gone)
             .To(51).Next().Is(EReady::Gone);
     }
 }
diff --git a/ydb/core/tablet_flat/ut/ut_redo.cpp b/ydb/core/tablet_flat/ut/ut_redo.cpp
index 73271b44036..95523535f04 100644
--- a/ydb/core/tablet_flat/ut/ut_redo.cpp
+++ b/ydb/core/tablet_flat/ut/ut_redo.cpp
@@ -26,8 +26,8 @@ Y_UNIT_TEST_SUITE(Redo) {
             .Col(0, 5,  ETypes::String)
             .Key({ 1 });
 
-        const auto foo = *TNatural(*lay).Col("foo", 33_u64);
-        const auto bar = *TNatural(*lay).Col("bar", 11_u64);
+        const auto foo = *TSchemedCookRow(*lay).Col("foo", 33_u64);
+        const auto bar = *TSchemedCookRow(*lay).Col("bar", 11_u64);
 
         const auto raw = NResource::Find("abi/008_basics_db.redo");
 
diff --git a/ydb/core/tablet_flat/ut/ut_self.cpp b/ydb/core/tablet_flat/ut/ut_self.cpp
index 5cf8efb163c..116cec7796b 100644
--- a/ydb/core/tablet_flat/ut/ut_self.cpp
+++ b/ydb/core/tablet_flat/ut/ut_self.cpp
@@ -24,8 +24,8 @@ Y_UNIT_TEST_SUITE(Self) {
             .Key({0, 1});
 
         auto put = *TPut().Do(0, "foo").Do<double>(2, 3.14).Do<ui32>(1, 42);
-        auto natTail = *TNatural(*lay).Col("foo", 42_u32, 3.14);
-        auto natNull = *TNatural(*lay).Col("foo", 42_u32, 3.14, nullptr);
+        auto natTail = *TSchemedCookRow(*lay).Col("foo", 42_u32, 3.14);
+        auto natNull = *TSchemedCookRow(*lay).Col("foo", 42_u32, 3.14, nullptr);
 
         /*_ Different binary rows representations should have the same
             textual output. Along with check that test rows wrappers