Index: core/kernel/utility/validator.php
===================================================================
--- core/kernel/utility/validator.php
+++ core/kernel/utility/validator.php
@@ -331,8 +331,20 @@
 
 		$res_temp = $this->Conn->GetOne( str_replace('%s', $this->dataSource->TableName, $sql) );
 
-		$current_table_only = getArrayValue($params, 'current_table_only'); // check unique record only in current table
-		$res_live = $current_table_only ? 0 : $this->Conn->GetOne( str_replace('%s', $this->Application->GetLiveName($this->dataSource->TableName), $sql) );
+		if ( getArrayValue($params, 'current_table_only') || !$this->dataSource->IsTempTable() ) {
+			// Check unique record only in current table.
+			$res_live = 0;
+		}
+		else {
+			$deleted_ids = $this->getTempTableDeletedIDs();
+			$live_sql = str_replace('%s', $this->Application->GetLiveName($this->dataSource->TableName), $sql);
+
+			if ( $deleted_ids ) {
+				$live_sql .= ' AND (' . $this->dataSource->IDField . ' NOT IN (' . implode(',', $deleted_ids) . '))';
+			}
+
+			$res_live = $this->Conn->GetOne($live_sql);
+		}
 
 		$res = ($res_temp == 0) && ($res_live == 0);
 
@@ -346,6 +358,56 @@
 	}
 
 	/**
+	 * Returns IDs deleted in temp table.
+	 *
+	 * @return array
+	 */
+	protected function getTempTableDeletedIDs()
+	{
+		$parent_prefix = $this->Application->getUnitOption($this->dataSource->Prefix, 'ParentPrefix');
+
+		if ( !$parent_prefix ) {
+			return array();
+		}
+
+		// 1. Get main IDs, that are edited in temp table.
+		$parent_table_name = $this->Application->GetTempName(
+			$this->Application->getUnitOption($parent_prefix, 'TableName'),
+			'prefix:' . $parent_prefix
+		);
+
+		$sql = 'SELECT ' . $this->Application->getUnitOption($parent_prefix, 'IDField') . '
+				FROM ' . $parent_table_name;
+		$parent_temp_ids = $this->Conn->GetCol($sql);
+
+		// Main item not saved to db, but sub-item is validated (only possible via custom code).
+		if ( !$parent_temp_ids ) {
+			return array();
+		}
+
+		// 2. From above found IDs find sub-item IDs in LIVE table.
+		$foreign_key = $this->Application->getUnitOption($this->dataSource->Prefix, 'ForeignKey');
+		$foreign_key = is_array($foreign_key) ? $foreign_key[$parent_prefix] : $foreign_key;
+
+		$sql = 'SELECT ' . $this->dataSource->IDField . '
+				FROM ' . $this->Application->GetLiveName($this->dataSource->TableName) . '
+				WHERE ' . $foreign_key . ' IN (' . implode(',', $parent_temp_ids) . ')';
+		$live_ids = $this->Conn->GetCol($sql);
+
+		// Sub-items were never saved to LIVE table.
+		if ( !$live_ids ) {
+			return array();
+		}
+
+		// 3. Return IDs of LIVE table, that are no longer present (deleted) in TEMP table.
+		$sql = 'SELECT ' . $this->dataSource->IDField . '
+				FROM ' . $this->dataSource->TableName;
+		$temp_ids = $this->Conn->GetCol($sql);
+
+		return array_diff($live_ids, $temp_ids);
+	}
+
+	/**
 	 * Check field value by user-defined alghoritm
 	 *
 	 * @param string $field field name