diff --git a/core/lib/Drupal/Core/Database/Driver/mysql/Schema.php b/core/lib/Drupal/Core/Database/Driver/mysql/Schema.php
index 8f8e3df..f3cc3ff 100644
--- a/core/lib/Drupal/Core/Database/Driver/mysql/Schema.php
+++ b/core/lib/Drupal/Core/Database/Driver/mysql/Schema.php
@@ -490,6 +490,13 @@ public function dropUniqueKey($table, $name) {
    * {@inheritdoc}
    */
   public function addIndex($table, $name, $fields, array $spec) {
+    if (!$this->tableExists($table)) {
+      throw new SchemaObjectDoesNotExistException(t("Cannot add index @name to table @table: table doesn't exist.", array('@table' => $table, '@name' => $name)));
+    }
+    if ($this->indexExists($table, $name)) {
+      throw new SchemaObjectExistsException(t("Cannot add index @name to table @table: index already exists.", array('@table' => $table, '@name' => $name)));
+    }
+
     $spec['indexes'][$name] = $fields;
     $indexes = $this->getNormalizedIndexes($spec);
 
diff --git a/core/lib/Drupal/Core/Database/Driver/pgsql/Schema.php b/core/lib/Drupal/Core/Database/Driver/pgsql/Schema.php
index cfbf43a..07f504c 100644
--- a/core/lib/Drupal/Core/Database/Driver/pgsql/Schema.php
+++ b/core/lib/Drupal/Core/Database/Driver/pgsql/Schema.php
@@ -641,6 +641,13 @@ public function dropUniqueKey($table, $name) {
    * {@inheritdoc}
    */
   public function addIndex($table, $name, $fields, array $spec) {
+    if (!$this->tableExists($table)) {
+      throw new SchemaObjectDoesNotExistException(t("Cannot add index @name to table @table: table doesn't exist.", array('@table' => $table, '@name' => $name)));
+    }
+    if ($this->indexExists($table, $name)) {
+      throw new SchemaObjectExistsException(t("Cannot add index @name to table @table: index already exists.", array('@table' => $table, '@name' => $name)));
+    }
+
     $spec['indexes'][$name] = $fields;
     $this->validateIndex($table, $name);
 
@@ -778,7 +785,7 @@ protected function _createKeys($table, $new_keys) {
     }
     if (isset($new_keys['indexes'])) {
       foreach ($new_keys['indexes'] as $name => $fields) {
-        $this->addIndex($table, $name, $fields);
+        $this->addIndex($table, $name, $fields, $new_keys);
       }
     }
   }
diff --git a/core/lib/Drupal/Core/Database/Driver/sqlite/Schema.php b/core/lib/Drupal/Core/Database/Driver/sqlite/Schema.php
index 89c98d5..9ef0750 100644
--- a/core/lib/Drupal/Core/Database/Driver/sqlite/Schema.php
+++ b/core/lib/Drupal/Core/Database/Driver/sqlite/Schema.php
@@ -586,6 +586,13 @@ protected function mapKeyDefinition(array $key_definition, array $mapping) {
    * {@inheritdoc}
    */
   public function addIndex($table, $name, $fields, array $spec) {
+    if (!$this->tableExists($table)) {
+      throw new SchemaObjectDoesNotExistException(t("Cannot add index @name to table @table: table doesn't exist.", array('@table' => $table, '@name' => $name)));
+    }
+    if ($this->indexExists($table, $name)) {
+      throw new SchemaObjectExistsException(t("Cannot add index @name to table @table: index already exists.", array('@table' => $table, '@name' => $name)));
+    }
+
     $spec['indexes'][$name] = $fields;
     $this->validateIndex($table, $name);
 
diff --git a/core/lib/Drupal/Core/Database/Schema.php b/core/lib/Drupal/Core/Database/Schema.php
index e7cf65d..45c7e5a 100644
--- a/core/lib/Drupal/Core/Database/Schema.php
+++ b/core/lib/Drupal/Core/Database/Schema.php
@@ -424,32 +424,6 @@ public function fieldExists($table, $column) {
    */
   abstract public function addIndex($table, $name, $fields, array $spec);
 
-
-  /**
-   * Validates whether the index is valid.
-   *
-   * This method ensures that the table exists, that the new index was specified
-   * and that there is no index with the same name yet.
-   *
-   * @param string $table
-   *   The table of the index name.
-   * @param string $name
-   *   The name of the index.
-   *
-   * @throws \Drupal\Core\Database\SchemaObjectDoesNotExistException
-   *   If the specified table doesn't exist.
-   * @throws \Drupal\Core\Database\SchemaObjectExistsException
-   *   If the specified table already has an index by that name.
-   */
-  protected function validateIndex($table, $name) {
-    if (!$this->tableExists($table)) {
-      throw new SchemaObjectDoesNotExistException("Cannot add index '$name' to table '$table': table doesn't exist.");
-    }
-    if ($this->indexExists($table, $name)) {
-      throw new SchemaObjectExistsException("Cannot add index '$name' to table '$table': index already exists.");
-    }
-  }
-
   /**
    * Gets normalized indexes from a table specification.
    *