diff --git a/public/index.php b/public/index.php
index 4256b0d..7bf22d6 100644
--- a/public/index.php
+++ b/public/index.php
@@ -173,15 +173,17 @@ $app->post('/api/table/update', function (Request $request, Response $response)
         $schema  = $payload['schema'];
         $table   = $payload['table'];
         $row     = $payload['row'];
+        $originalRow = $payload['originalRow'] ?? null;
         $metaArr = $meta->getTableMeta($schema, $table);
 
-        $result = $ds->updateRow($schema, $table, $row, $metaArr['columns'], $metaArr['primaryKey']);
+        $result = $ds->updateRow($schema, $table, $row, $metaArr['columns'], $metaArr['primaryKey'], $originalRow);
         $response->getBody()->write(json_encode($result));
         return $response->withHeader('Content-Type', 'application/json');
     } catch (\Exception $e) {
         $error = ['error' => true, 'message' => $e->getMessage()];
         $response->getBody()->write(json_encode($error));
-        return $response->withHeader('Content-Type', 'application/json')->withStatus(400);
+        $status = ((int)$e->getCode() === 409 || str_starts_with($e->getMessage(), 'CONFLICT:')) ? 409 : 400;
+        return $response->withHeader('Content-Type', 'application/json')->withStatus($status);
     }
 });
 
diff --git a/public/js/core.js b/public/js/core.js
index 30aa27d..c0dc362 100644
--- a/public/js/core.js
+++ b/public/js/core.js
@@ -27,7 +27,9 @@ async function api(url, method = 'GET', body) {
 
   if (!res.ok) {
     // Сервер вернул JSON с ошибкой
-    throw new Error(data.message || data.error || 'Неизвестная ошибка');
+    const rawMessage = data.message || data.error || 'Неизвестная ошибка';
+    const cleanMessage = String(rawMessage).replace(/^CONFLICT:\s*/i, '');
+    throw new Error(cleanMessage);
   }
 
   // Проверяем на ошибку в успешном ответе
diff --git a/public/js/operations.js b/public/js/operations.js
index 58a355b..8480a42 100644
--- a/public/js/operations.js
+++ b/public/js/operations.js
@@ -806,7 +806,8 @@ async function showEditModal(selectedRows) {
           await api('/api/table/update', 'POST', {
             schema: currentSchema,
             table: currentTable,
-            row: updatedRow
+            row: updatedRow,
+            originalRow: row
           });
           updated++;
         } catch (err) {
diff --git a/public/js/table.js b/public/js/table.js
index d3d1cc1..a32ce99 100644
--- a/public/js/table.js
+++ b/public/js/table.js
@@ -566,7 +566,7 @@ async function selectTable(schema, tableName, restoreState = false) {
   });
 
   // Функция сохранения строки
-  async function saveRow(rowPos, rowData, rowElement) {
+  async function saveRow(rowPos, rowData, rowElement, originalRowData = null) {
     console.log('💾 === СОХРАНЕНИЕ ===');
     console.log('  Data:', rowData);
 
@@ -581,7 +581,8 @@ async function selectTable(schema, tableName, restoreState = false) {
       const result = await api('/api/table/update', 'POST', {
         schema: currentSchema,
         table: currentTable,
-        row: rowData
+        row: rowData,
+        originalRow: originalRowData || rowData
       });
 
       console.log('✅ СОХРАНЕНО:', result);
@@ -694,9 +695,11 @@ async function selectTable(schema, tableName, restoreState = false) {
       clearTimeout(dirtyRows.get(rowPos).timeout);
     }
 
+    const originalRowData = { ...rowData, [cell.getField()]: oldValue };
+
     const timeout = setTimeout(async () => {
       console.log('⏰ Автосохранение...');
-      await saveRow(rowPos, rowData, row);
+      await saveRow(rowPos, rowData, row, originalRowData);
     }, 2000);
 
     dirtyRows.set(rowPos, { data: rowData, element: row, timeout: timeout });
diff --git a/src/DataService.php b/src/DataService.php
index c30043b..e31353b 100644
--- a/src/DataService.php
+++ b/src/DataService.php
@@ -209,7 +209,7 @@ private function formatPDOError(\PDOException $e, string $schema, string $table,
 }
 
 
-public function updateRow(string $schema, string $table, array $row, array $columns, array $pk): array
+public function updateRow(string $schema, string $table, array $row, array $columns, array $pk, ?array $originalRow = null): array
 {
     $schema = $this->validateIdentifier($schema, 'schema');
     $table = $this->validateIdentifier($table, 'table');
@@ -248,6 +248,22 @@ public function updateRow(string $schema, string $table, array $row, array $colu
         $params[":pk_$name"] = $row[$name];
     }
 
+    $trackedColumns = [];
+    if (is_array($originalRow)) {
+        foreach ($columns as $c) {
+            $name = $this->validateIdentifier((string)$c['COLUMN_NAME'], 'column');
+            if (in_array($name, $pk, true)) {
+                continue;
+            }
+            if (!array_key_exists($name, $originalRow)) {
+                continue;
+            }
+            $whereParts[] = "`$name` <=> :orig_$name";
+            $params[":orig_$name"] = $originalRow[$name];
+            $trackedColumns[] = $name;
+        }
+    }
+
     $sql = sprintf(
         "UPDATE `%s`.`%s` SET %s WHERE %s",
         $schema, $table,
@@ -262,6 +278,44 @@ public function updateRow(string $schema, string $table, array $row, array $colu
         $stmt->execute($params);
         $rowCount = $stmt->rowCount();
         error_log("Rows updated: $rowCount");
+
+        if ($rowCount === 0 && !empty($trackedColumns)) {
+            $pkWhere = [];
+            $selectParams = [];
+            foreach ($pk as $name) {
+                $name = $this->validateIdentifier((string)$name, 'column');
+                $pkWhere[] = "`$name` = :pk_$name";
+                $selectParams[":pk_$name"] = $row[$name];
+            }
+
+            $selectedColumns = array_merge($pk, $trackedColumns);
+            $selectSql = sprintf(
+                "SELECT %s FROM `%s`.`%s` WHERE %s LIMIT 1",
+                implode(', ', array_map(fn($col) => "`$col`", $selectedColumns)),
+                $schema,
+                $table,
+                implode(' AND ', $pkWhere)
+            );
+            $selectStmt = $this->pdo->prepare($selectSql);
+            $selectStmt->execute($selectParams);
+            $currentRow = $selectStmt->fetch(PDO::FETCH_ASSOC);
+
+            if ($currentRow === false) {
+                throw new \RuntimeException('CONFLICT: Запись была удалена другим пользователем.', 409);
+            }
+
+            foreach ($trackedColumns as $name) {
+                $expected = $originalRow[$name] ?? null;
+                $actual = $currentRow[$name] ?? null;
+                if ($expected != $actual) {
+                    throw new \RuntimeException(
+                        'CONFLICT: Запись была изменена в другой сессии. Обновите таблицу и повторите.',
+                        409
+                    );
+                }
+            }
+        }
+
         return ['updated' => $rowCount];
     } catch (\PDOException $e) {
         error_log("UPDATE FAILED: " . $e->getMessage());