diff --git a/core/modules/migrate/src/Plugin/Migration.php b/core/modules/migrate/src/Plugin/Migration.php
index 66ab6642cec6169846a6b349ed9343ca2ec83bb3..021edfd6ba725a841c37e99c4e13c0c7ed26ee75 100644
--- a/core/modules/migrate/src/Plugin/Migration.php
+++ b/core/modules/migrate/src/Plugin/Migration.php
@@ -96,7 +96,7 @@ class Migration extends PluginBase implements MigrationInterface, RequirementsIn
    *
    * Used to initialize $idMapPlugin.
    *
-   * @var string
+   * @var array
    */
   protected $idMap = [];
 
diff --git a/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php b/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
index 6ecc8ed4ea65b7b22f7212a94827ce5e0145399c..d0f31ffa0b4e45ebd2754fb0dace279372ba7164 100644
--- a/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
+++ b/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
@@ -111,9 +111,9 @@ class Sql extends PluginBase implements MigrateIdMapInterface, ContainerFactoryP
   /**
    * The result.
    *
-   * @var null
+   * @var \Drupal\Core\Database\StatementInterface
    */
-  protected $result = NULL;
+  protected $result;
 
   /**
    * The source identifiers.
@@ -132,7 +132,7 @@ class Sql extends PluginBase implements MigrateIdMapInterface, ContainerFactoryP
   /**
    * The current row.
    *
-   * @var null
+   * @var array|false|null
    */
   protected $currentRow = NULL;