diff --git a/core/lib/Drupal/Core/Database/Driver/sqlite/Connection.php b/core/lib/Drupal/Core/Database/Driver/sqlite/Connection.php
index 0f9a4d25..7bb6f492 100644
--- a/core/lib/Drupal/Core/Database/Driver/sqlite/Connection.php
+++ b/core/lib/Drupal/Core/Database/Driver/sqlite/Connection.php
@@ -35,6 +35,16 @@ class Connection extends DatabaseConnection {
     'NOT LIKE BINARY' => ['postfix' => " ESCAPE '\\'", 'operator' => 'NOT GLOB'],
   ];
 
+  /**
+   * Names of database attached to the main database.
+   *
+   * If a table prefix is specified, a database with the prefix name is
+   * attached.
+   *
+   * @var array
+   */
+  protected $attachedDatabases = [];
+
   /**
    * Whether or not a table has been dropped this request: the destructor will
    * only try to get rid of unnecessary databases if there is potential of them
@@ -43,11 +53,6 @@ class Connection extends DatabaseConnection {
    * This variable is set to public because Schema needs to
    * access it. However, it should not be manually set.
    *
-   * @deprecated in Drupal 9.0.0 and will be removed before Drupal 10.0.0.
-   * This variable has become irrelevant because Drupal no longer supports
-   * attaching to other SQLite databases. Instead create another database
-   * connection for the other SQLite database.
-   *
    * @var bool
    */
   public $tableDropped = FALSE;
@@ -66,6 +71,29 @@ public function __construct(\PDO $connection, array $connection_options) {
     $this->transactionSupport = $this->transactionalDDLSupport = !isset($connection_options['transactions']) || $connection_options['transactions'] !== FALSE;
 
     $this->connectionOptions = $connection_options;
+
+    // Attach a database if a prefix is defined.
+    $prefix = $this->getPrefix();
+    // Empty prefix means query the main database -- no need to attach anything.
+    if (!empty($prefix)) {
+      // Only attach the database once.
+      if (!isset($this->attachedDatabases[$prefix])) {
+        $this->attachedDatabases[$prefix] = $prefix;
+        if ($connection_options['database'] === ':memory:') {
+         // In memory database use ':memory:' as database name. According to
+          // http://www.sqlite.org/inmemorydb.html it will open a unique
+          // database so attaching it twice is not a problem.
+          $this->query('ATTACH DATABASE :database AS :prefix', [':database' => $connection_options['database'], ':prefix' => $prefix]);
+        }
+        else {
+          $this->query('ATTACH DATABASE :database AS :prefix', [':database' => $connection_options['database'] . '-' . $prefix, ':prefix' => $prefix]);
+        }
+      }
+
+      // Add a ., so queries become prefix.table, which is proper syntax for
+      // querying an attached database.
+      $this->setPrefix($prefix . '.');
+    }
   }
 
   /**
@@ -136,12 +164,37 @@ public static function open(array &$connection_options = []) {
   }
 
   /**
-   * Gets all the attached databases.
+   * Destructor for the SQLite connection.
    *
-   * @deprecated in Drupal 9.0.0 and will be removed before Drupal 10.0.0.
-   * This method has become irrelevant because Drupal no longer supports
-   * attaching to other SQLite databases. Instead create another database
-   * connection for the other SQLite database.
+   * We prune empty databases on destruct, but only if tables have been
+   * dropped. This is especially needed when running the test suite, which
+   * creates and destroy databases several times in a row.
+   */
+  public function __destruct() {
+    if ($this->tableDropped && !empty($this->attachedDatabases)) {
+      foreach ($this->attachedDatabases as $prefix) {
+       // Check if the database is now empty, ignore the internal SQLite tables.
+        try {
+          $count = $this->query('SELECT COUNT(*) FROM ' . $prefix . '.sqlite_master WHERE type = :type AND name NOT LIKE :pattern', [':type' => 'table', ':pattern' => 'sqlite_%'])->fetchField();
+
+          // We can prune the database file if it doesn't have any tables.
+          if ($count == 0) {
+            // Detaching the database fails at this point, but no other queries
+            // are executed after the connection is destructed so we can simply
+            // remove the database file.
+            unlink($this->connectionOptions['database'] . '-' . $prefix);
+          }
+        }
+        catch (\Exception $e) {
+          // Ignore the exception and continue. There is nothing we can do here
+          // to report the error or fail safe.
+        }
+      }
+    }
+  }
+
+  /**
+   * Gets all the attached databases.
    *
    * @return array
    *   An array of attached database names.
@@ -149,7 +202,7 @@ public static function open(array &$connection_options = []) {
    * @see \Drupal\Core\Database\Driver\sqlite\Connection::__construct()
    */
   public function getAttachedDatabases() {
-    return [];
+    return $this->attachedDatabases;
   }
 
   /**