diff --git a/ydb/core/tx/schemeshard/ut_backup/ut_backup.cpp b/ydb/core/tx/schemeshard/ut_backup/ut_backup.cpp
index 53bd14fa3576..0327648b86d3 100644
--- a/ydb/core/tx/schemeshard/ut_backup/ut_backup.cpp
+++ b/ydb/core/tx/schemeshard/ut_backup/ut_backup.cpp
@@ -73,11 +73,11 @@ Y_UNIT_TEST_SUITE(TBackupTests) {
 
         Backup(runtime, ToString(Codec), R"(
             Name: "Table"
-            Columns { Name: "key" Type: "Utf8" }
+            Columns { Name: "key" Type: "Uint32" }
             Columns { Name: "value" Type: "Utf8" }
             KeyColumnNames: ["key"]
         )", [](TTestBasicRuntime& runtime) {
-            WriteRow(runtime, "a", "valueA");
+            UpdateRow(runtime, "Table", 1, "valueA");
         });
     }
 
@@ -86,17 +86,17 @@ Y_UNIT_TEST_SUITE(TBackupTests) {
 
         Backup(runtime, ToString(Codec), R"(
             Name: "Table"
-            Columns { Name: "key" Type: "Utf8" }
+            Columns { Name: "key" Type: "Uint32" }
             Columns { Name: "value" Type: "Utf8" }
             KeyColumnNames: ["key"]
             SplitBoundary {
               KeyPrefix {
-                Tuple { Optional { Text: "b" } }
+                Tuple { Optional { Uint32: 2 } }
               }
             }
         )", [](TTestBasicRuntime& runtime) {
-            WriteRow(runtime, "a", "valueA", TTestTxConfig::FakeHiveTablets + 0);
-            WriteRow(runtime, "b", "valueb", TTestTxConfig::FakeHiveTablets + 1);
+            UpdateRow(runtime, "Table", 1, "valueA", TTestTxConfig::FakeHiveTablets + 0);
+            UpdateRow(runtime, "Table", 2, "valueb", TTestTxConfig::FakeHiveTablets + 1);
         });
     }
 
@@ -107,12 +107,12 @@ Y_UNIT_TEST_SUITE(TBackupTests) {
 
         const auto actualResult = Backup(runtime, ToString(Codec), R"(
             Name: "Table"
-            Columns { Name: "key" Type: "Utf8" }
+            Columns { Name: "key" Type: "Uint32" }
             Columns { Name: "value" Type: "Utf8" }
             KeyColumnNames: ["key"]
         )", [](TTestBasicRuntime& runtime) {
             for (ui32 i = 0; i < 100 * batchSize; ++i) {
-                WriteRow(runtime, Sprintf("a%d", i), "valueA");
+                UpdateRow(runtime, "Table", i, "valueA");
             }
         }, batchSize, minWriteBatchSize);
 
diff --git a/ydb/core/tx/schemeshard/ut_export/ut_export.cpp b/ydb/core/tx/schemeshard/ut_export/ut_export.cpp
index 0c0e396adf9b..4a8ad8b32170 100644
--- a/ydb/core/tx/schemeshard/ut_export/ut_export.cpp
+++ b/ydb/core/tx/schemeshard/ut_export/ut_export.cpp
@@ -687,14 +687,14 @@ partitioning_settings {
 
         TestCreateTable(runtime, ++txId, "/MyRoot", R"(
             Name: "Table"
-            Columns { Name: "key" Type: "Utf8" }
+            Columns { Name: "key" Type: "Uint32" }
             Columns { Name: "value" Type: "Utf8" }
             KeyColumnNames: ["key"]
         )");
         env.TestWaitNotification(runtime, txId);
 
-        WriteRow(runtime, "a", "valueA");
-        WriteRow(runtime, "b", "valueB");
+        UpdateRow(runtime, "Table", 1, "valueA");
+        UpdateRow(runtime, "Table", 2, "valueB");
 
         runtime.SetLogPriority(NKikimrServices::S3_WRAPPER, NActors::NLog::PRI_TRACE);
         runtime.SetLogPriority(NKikimrServices::DATASHARD_BACKUP, NActors::NLog::PRI_TRACE);
@@ -827,14 +827,14 @@ partitioning_settings {
 
         TestCreateTable(runtime, ++txId, "/MyRoot", R"(
             Name: "Table"
-            Columns { Name: "key" Type: "Utf8" }
+            Columns { Name: "key" Type: "Uint32" }
             Columns { Name: "value" Type: "Utf8" }
             KeyColumnNames: ["key"]
         )");
         env.TestWaitNotification(runtime, txId);
 
         for (int i = 1; i < 500; ++i) {
-            WriteRow(runtime, Sprintf("a%i", i), "value");
+            UpdateRow(runtime, "Table", i, "value");
         }
 
         // trigger memtable's compaction
@@ -925,13 +925,13 @@ partitioning_settings {
 
         TestCreateTable(runtime, ++txId, "/MyRoot", R"(
             Name: "Table"
-            Columns { Name: "key" Type: "Utf8" }
+            Columns { Name: "key" Type: "Uint32" }
             Columns { Name: "value" Type: "Utf8" }
             KeyColumnNames: ["key"]
         )");
         env.TestWaitNotification(runtime, txId);
 
-        WriteRow(runtime, "a", "valueA");
+        UpdateRow(runtime, "Table", 1, "valueA");
 
         TPortManager portManager;
         const ui16 port = portManager.GetPort();
@@ -1277,14 +1277,14 @@ partitioning_settings {
 
         TestCreateTable(runtime, ++txId, "/MyRoot", R"(
             Name: "Table"
-            Columns { Name: "key" Type: "Utf8" }
+            Columns { Name: "key" Type: "Uint32" }
             Columns { Name: "value" Type: "Utf8" }
             KeyColumnNames: ["key"]
         )");
         env.TestWaitNotification(runtime, txId);
 
-        WriteRow(runtime, "a", "valueA");
-        WriteRow(runtime, "b", "valueB");
+        UpdateRow(runtime, "Table", 1, "valueA");
+        UpdateRow(runtime, "Table", 2, "valueB");
         runtime.SetLogPriority(NKikimrServices::DATASHARD_BACKUP, NActors::NLog::PRI_DEBUG);
 
         TPortManager portManager;
diff --git a/ydb/core/tx/schemeshard/ut_helpers/helpers.cpp b/ydb/core/tx/schemeshard/ut_helpers/helpers.cpp
index 8f292a6810de..76879b55d259 100644
--- a/ydb/core/tx/schemeshard/ut_helpers/helpers.cpp
+++ b/ydb/core/tx/schemeshard/ut_helpers/helpers.cpp
@@ -2,6 +2,8 @@
 
 #include <ydb/core/engine/mkql_proto.h>
 #include <ydb/core/engine/minikql/flat_local_tx_factory.h>
+#include <ydb/core/tx/data_events/events.h>
+#include <ydb/core/tx/data_events/payload_helper.h>
 #include <ydb/core/tx/schemeshard/schemeshard.h>
 #include <ydb/core/tx/tx_proxy/proxy.h>
 #include <ydb/core/persqueue/events/global.h>
@@ -2256,31 +2258,31 @@ namespace NSchemeShardUT_Private {
         NKikimr::NPQ::CmdWrite(&runtime, tabletId, edge, partitionId, "sourceid0", msgSeqNo, data, false, {}, true, cookie, 0);
     }
 
-    void WriteRow(TTestActorRuntime& runtime, const TString& key, const TString& value, ui64 tabletId) {
+    void UpdateRow(TTestActorRuntime& runtime, const TString& table, const ui32 key, const TString& value, ui64 tabletId) {
         NKikimrMiniKQL::TResult result;
         TString error;
         NKikimrProto::EReplyStatus status = LocalMiniKQL(runtime, tabletId, Sprintf(R"(
             (
-                (let key '( '('key (Utf8 '%s) ) ) )
+                (let key '( '('key (Uint32 '%d) ) ) )
                 (let row '( '('value (Utf8 '%s) ) ) )
-                (return (AsList (UpdateRow '__user__Table key row) ))
+                (return (AsList (UpdateRow '__user__%s key row) ))
             )
-        )", key.c_str(), value.c_str()), result, error);
+        )", key, value.c_str(), table.c_str()), result, error);
 
         UNIT_ASSERT_VALUES_EQUAL_C(status, NKikimrProto::EReplyStatus::OK, error);
         UNIT_ASSERT_VALUES_EQUAL(error, "");
     }
 
-    void WriteRowPg(TTestActorRuntime& runtime, const TString& key, ui32 value, ui64 tabletId) {
+    void UpdateRowPg(TTestActorRuntime& runtime, const TString& table, const ui32 key, ui32 value, ui64 tabletId) {
         NKikimrMiniKQL::TResult result;
         TString error;
         NKikimrProto::EReplyStatus status = LocalMiniKQL(runtime, tabletId, Sprintf(R"(
             (
-                (let key '( '('key (Utf8 '%s) ) ) )
+                (let key '( '('key (Utf8 '%d) ) ) )
                 (let row '( '('value (PgConst '%u (PgType 'int4)) ) ) )
-                (return (AsList (UpdateRow '__user__Table key row) ))
+                (return (AsList (UpdateRow '__user__%s key row) ))
             )
-        )", key.c_str(), value), result, error);
+        )", key, value, table.c_str()), result, error);
 
         UNIT_ASSERT_VALUES_EQUAL_C(status, NKikimrProto::EReplyStatus::OK, error);
         UNIT_ASSERT_VALUES_EQUAL(error, "");
@@ -2291,6 +2293,7 @@ namespace NSchemeShardUT_Private {
         auto tableDesc = DescribePath(runtime, tablePath, true, true);
         const auto& tablePartitions = tableDesc.GetPathDescription().GetTablePartitions();
         UNIT_ASSERT(partitionIdx < tablePartitions.size());
+        const ui64 datashardTabletId = tablePartitions[partitionIdx].GetDatashardId();
 
         auto ev = MakeHolder<TEvDataShard::TEvUploadRowsRequest>();
         ev->Record.SetTableId(tableDesc.GetPathId());
@@ -2314,7 +2317,34 @@ namespace NSchemeShardUT_Private {
         }
 
         const auto& sender = runtime.AllocateEdgeActor();
-        ForwardToTablet(runtime, tablePartitions[partitionIdx].GetDatashardId(), sender, ev.Release());
+        ForwardToTablet(runtime, datashardTabletId, sender, ev.Release());
         runtime.GrabEdgeEvent<TEvDataShard::TEvUploadRowsResponse>(sender);
     }
+
+    void WriteRow(TTestActorRuntime& runtime, const ui64 txId, const TString& tablePath, int partitionIdx, const ui32 key, const TString& value, bool successIsExpected) {
+        auto tableDesc = DescribePath(runtime, tablePath, true, true);
+        const auto& tablePartitions = tableDesc.GetPathDescription().GetTablePartitions();
+        UNIT_ASSERT(partitionIdx < tablePartitions.size());
+        const ui64 tableId = tableDesc.GetPathId();
+        const ui64 datashardTabletId = tablePartitions[partitionIdx].GetDatashardId();
+
+        const auto& sender = runtime.AllocateEdgeActor();
+
+        std::vector<ui32> columnIds{1, 2};
+
+        TVector<TCell> cells{TCell((const char*)&key, sizeof(ui32)), TCell(value.c_str(), value.size())};
+
+        TSerializedCellMatrix matrix(cells, 1, 2);
+
+        auto evWrite = std::make_unique<NKikimr::NEvents::TDataEvents::TEvWrite>(txId, NKikimrDataEvents::TEvWrite::MODE_IMMEDIATE);
+        ui64 payloadIndex = NKikimr::NEvWrite::TPayloadHelper<NKikimr::NEvents::TDataEvents::TEvWrite>(*evWrite).AddDataToPayload(std::move(matrix.ReleaseBuffer()));
+        evWrite->AddOperation(NKikimrDataEvents::TEvWrite::TOperation::OPERATION_UPSERT, tableId, 1, columnIds, payloadIndex, NKikimrDataEvents::FORMAT_CELLVEC);
+
+        ForwardToTablet(runtime, datashardTabletId, sender, evWrite.release());
+
+        auto ev = runtime.GrabEdgeEventRethrow<NEvents::TDataEvents::TEvWriteResult>(sender);
+        auto status = ev->Get()->Record.GetStatus();
+
+        UNIT_ASSERT_C(successIsExpected == (status == NKikimrDataEvents::TEvWriteResult::STATUS_COMPLETED), "Status: " << ev->Get()->Record.GetStatus() << " Issues: " << ev->Get()->Record.GetIssues());
+    }
 }
diff --git a/ydb/core/tx/schemeshard/ut_helpers/helpers.h b/ydb/core/tx/schemeshard/ut_helpers/helpers.h
index 960f228fa3ef..6dd806cfd179 100644
--- a/ydb/core/tx/schemeshard/ut_helpers/helpers.h
+++ b/ydb/core/tx/schemeshard/ut_helpers/helpers.h
@@ -546,8 +546,9 @@ namespace NSchemeShardUT_Private {
 
     void SendTEvPeriodicTopicStats(TTestActorRuntime& runtime, ui64 topicId, ui64 generation, ui64 round, ui64 dataSize, ui64 usedReserveSize);
     void WriteToTopic(TTestActorRuntime& runtime, const TString& path, ui32& msgSeqNo, const TString& message);
-    void WriteRow(TTestActorRuntime& runtime, const TString& key, const TString& value, ui64 tabletId = TTestTxConfig::FakeHiveTablets);
-    void WriteRowPg(TTestActorRuntime& runtime, const TString& key, ui32 value, ui64 tabletId = TTestTxConfig::FakeHiveTablets);
+    void UpdateRow(TTestActorRuntime& runtime, const TString& table, const ui32 key, const TString& value, ui64 tabletId = TTestTxConfig::FakeHiveTablets);
+    void UpdateRowPg(TTestActorRuntime& runtime, const TString& table, const ui32 key, ui32 value, ui64 tabletId = TTestTxConfig::FakeHiveTablets);
     void UploadRows(TTestActorRuntime& runtime, const TString& tablePath, int partitionIdx, const TVector<ui32>& keyTags, const TVector<ui32>& valueTags, const TVector<ui32>& recordIds);
+    void WriteRow(TTestActorRuntime& runtime, const ui64 txId, const TString& tablePath, int partitionIdx, const ui32 key, const TString& value, bool successIsExpected = true);
 
 } //NSchemeShardUT_Private
diff --git a/ydb/core/tx/schemeshard/ut_subdomain/ut_subdomain.cpp b/ydb/core/tx/schemeshard/ut_subdomain/ut_subdomain.cpp
index af8d11da6462..bbda860bc133 100644
--- a/ydb/core/tx/schemeshard/ut_subdomain/ut_subdomain.cpp
+++ b/ydb/core/tx/schemeshard/ut_subdomain/ut_subdomain.cpp
@@ -2816,21 +2816,6 @@ Y_UNIT_TEST_SUITE(TSchemeShardSubDomainTest) {
         TTestEnv env(runtime, opts);
         const auto sender = runtime.AllocateEdgeActor();
 
-        auto writeRow = [&](ui64 tabletId, ui32 key, const TString& value, const char* table) {
-            NKikimrMiniKQL::TResult result;
-            TString error;
-            NKikimrProto::EReplyStatus status = LocalMiniKQL(runtime, tabletId, Sprintf(R"(
-                (
-                    (let key   '( '('key (Uint32 '%u ) ) ) )
-                    (let row   '( '('value (Utf8 '%s) ) ) )
-                    (return (AsList (UpdateRow '__user__%s key row) ))
-                )
-            )", key, value.c_str(), table), result, error);
-
-            UNIT_ASSERT_VALUES_EQUAL_C(status, NKikimrProto::EReplyStatus::OK, error);
-            UNIT_ASSERT_VALUES_EQUAL(error, "");
-        };
-
         auto waitForTableStats = [&](ui32 shards) {
             TDispatchOptions options;
             options.FinalEvents.push_back(TDispatchOptions::TFinalEventCondition(TEvDataShard::EvPeriodicTableStats, shards));
@@ -2865,7 +2850,7 @@ Y_UNIT_TEST_SUITE(TSchemeShardSubDomainTest) {
             )", {NKikimrScheme::StatusAccepted});
             env.TestWaitNotification(runtime, txId);
 
-            writeRow(tabletId, 1, "value1", "Table1");
+            UpdateRow(runtime, "Table1", 1, "value1", tabletId);
             waitForTableStats(1);
 
             auto du = getDiskSpaceUsage();
@@ -2888,8 +2873,8 @@ Y_UNIT_TEST_SUITE(TSchemeShardSubDomainTest) {
             )", {NKikimrScheme::StatusAccepted});
             env.TestWaitNotification(runtime, txId);
 
-            writeRow(tabletId + 0, 1, "value1", "Table2");
-            writeRow(tabletId + 1, 2, "value2", "Table2");
+            UpdateRow(runtime, "Table2", 1, "value1", tabletId + 0);
+            UpdateRow(runtime, "Table2", 2, "value2", tabletId + 1);
             waitForTableStats(1 /* Table1 */ + 2 /* Table2 */);
 
             auto du = getDiskSpaceUsage();
@@ -2910,21 +2895,6 @@ Y_UNIT_TEST_SUITE(TSchemeShardSubDomainTest) {
         TTestEnv env(runtime, opts);
         ui64 txId = 100;
 
-        auto writeRow = [&](ui64 tabletId, ui32 key, const TString& value, const char* table) {
-            NKikimrMiniKQL::TResult result;
-            TString error;
-            NKikimrProto::EReplyStatus status = LocalMiniKQL(runtime, tabletId, Sprintf(R"(
-                (
-                    (let key   '( '('key (Uint32 '%u ) ) ) )
-                    (let row   '( '('value (Utf8 '%s) ) ) )
-                    (return (AsList (UpdateRow '__user__%s key row) ))
-                )
-            )", key, value.c_str(), table), result, error);
-
-            UNIT_ASSERT_VALUES_EQUAL_C(status, NKikimrProto::EReplyStatus::OK, error);
-            UNIT_ASSERT_VALUES_EQUAL(error, "");
-        };
-
         auto waitForTableStats = [&](ui32 shards) {
             TDispatchOptions options;
             options.FinalEvents.push_back(TDispatchOptions::TFinalEventCondition(TEvDataShard::EvPeriodicTableStats, shards));
@@ -2972,7 +2942,7 @@ Y_UNIT_TEST_SUITE(TSchemeShardSubDomainTest) {
                 )", {NKikimrScheme::StatusAccepted});
         env.TestWaitNotification(runtime, txId);
 
-        writeRow(tabletId, 1, "value1", "Table1");
+        UpdateRow(runtime, "Table1", 1, "value1", tabletId);
         waitForTableStats(1);
 
         TestDescribeResult(DescribePath(runtime, "/MyRoot/USER_0"),