diff -u b/core/tests/Drupal/KernelTests/Core/Database/SchemaTest.php b/core/tests/Drupal/KernelTests/Core/Database/SchemaTest.php
--- b/core/tests/Drupal/KernelTests/Core/Database/SchemaTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Database/SchemaTest.php
@@ -238,27 +238,6 @@
     $this->assertIndexOnColumns($table_name, ['id'], 'primary');
     $this->assertIndexOnColumns($table_name, ['test_field'], 'unique');
 
-    // Test for existing primary and unique keys.
-    switch ($db_type) {
-      case 'pgsql':
-        $primary_key_exists = (bool) $this->schema->queryFieldInformation($table_name, 'id', 'p');
-        $unique_key_exists = (bool) $this->schema->queryFieldInformation($table_name, 'test_field', 'u');
-        break;
-
-      case 'sqlite':
-        // SQLite does not create a standalone index for primary keys.
-        $primary_key_exists = TRUE;
-        $unique_key_exists = $this->schema->indexExists($table_name, 'test_field');
-        break;
-
-      default:
-        $primary_key_exists = $this->schema->indexExists($table_name, 'PRIMARY');
-        $unique_key_exists = $this->schema->indexExists($table_name, 'test_field');
-        break;
-    }
-    $this->assertIdentical($primary_key_exists, TRUE, 'Primary key created.');
-    $this->assertIdentical($unique_key_exists, TRUE, 'Unique key created.');
-
     $new_table_name = strtolower($this->getRandomGenerator()->name(63 - strlen($this->getDatabasePrefix())));
     $this->assertNull($this->schema->renameTable($table_name, $new_table_name));