diff --git a/.editorconfig b/.editorconfig
index 686c443c..2b58ad65 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -8,10 +8,13 @@ root = true
 [*]
 end_of_line = LF
 indent_style = space
-indent_size = 2
+indent_size = 4
 charset = utf-8
 trim_trailing_whitespace = true
 insert_final_newline = true
 
 [composer.{json,lock}]
 indent_size = 4
+
+[*.yml]
+indent_size = 2
diff --git a/config/runner.yml b/config/runner.yml
index efbc48d2..9d380200 100644
--- a/config/runner.yml
+++ b/config/runner.yml
@@ -37,6 +37,9 @@ drupal:
     config_dir: ~
     existing_config: false
     settings_override_file: "settings.override.php"
+    # Setting this to "false" will run "site-install" without the "--db-url" parameter.
+    # This is useful if the database settings are already set in your settings.php file.
+    generate_db_url: true
 
   # Administrator account information.
   account:
diff --git a/src/Commands/AbstractDrupalCommands.php b/src/Commands/AbstractDrupalCommands.php
index 2066e248..e74e4f30 100644
--- a/src/Commands/AbstractDrupalCommands.php
+++ b/src/Commands/AbstractDrupalCommands.php
@@ -186,6 +186,8 @@ public function siteInstall(array $options = [
             ->sitesSubdir($options['sites-subdir'])
             ->siteProfile($options['site-profile']);
 
+        $task->setGenerateDbUrl($this->getConfig()->get('drupal.site.generate_db_url'));
+
         if (!empty($options['existing-config'])) {
             $task->setExistingConfig($options['existing-config']);
         }
diff --git a/src/Tasks/Drush/Drush.php b/src/Tasks/Drush/Drush.php
index eb45332e..447e0d40 100644
--- a/src/Tasks/Drush/Drush.php
+++ b/src/Tasks/Drush/Drush.php
@@ -30,6 +30,7 @@ class Drush extends Exec
     protected $databaseName = '';
     protected $sitesSubdir = '';
     protected $existingConfig = false;
+    protected $generateDbUrl = true;
 
     /**
      * Build Drush site install command.
@@ -38,16 +39,6 @@ class Drush extends Exec
      */
     public function siteInstall()
     {
-        $dbArray = [
-            'scheme' => $this->databaseScheme,
-            'user' => $this->databaseUser,
-            'pass' => $this->databasePassword,
-            'host' => $this->databaseHost,
-            'port' => $this->databasePort,
-            'path' => $this->databaseName,
-        ];
-        $dbUrl = http_build_url($dbArray, $dbArray);
-
         $this->option('-y')
             ->rawArg("--root=$(pwd)/".$this->root)
             ->options([
@@ -58,9 +49,22 @@ public function siteInstall()
                 'account-name' => $this->accountName,
                 'account-pass' => $this->accountPassword,
                 'sites-subdir' => $this->sitesSubdir,
-                'db-url' => $dbUrl,
             ], '=');
 
+        if ($this->generateDbUrl) {
+            $dbArray = [
+                'scheme' => $this->databaseScheme,
+                'user' => $this->databaseUser,
+                'pass' => $this->databasePassword,
+                'host' => $this->databaseHost,
+                'port' => $this->databasePort,
+                'path' => $this->databaseName,
+            ];
+            $dbUrl = http_build_url($dbArray, $dbArray);
+
+            $this->option('db-url', $dbUrl, '=');
+        }
+
         if (!empty($this->existingConfig)) {
             $this->option('existing-config');
         }
@@ -271,4 +275,16 @@ public function setExistingConfig($existingConfig)
 
         return $this;
     }
+
+    /**
+     * @param bool $generateDbUrl
+     *
+     * @return Drush
+     */
+    public function setGenerateDbUrl($generateDbUrl)
+    {
+        $this->generateDbUrl = $generateDbUrl;
+
+        return $this;
+    }
 }
diff --git a/tests/fixtures/simulation.yml b/tests/fixtures/simulation.yml
index f046db43..434203e8 100644
--- a/tests/fixtures/simulation.yml
+++ b/tests/fixtures/simulation.yml
@@ -346,3 +346,13 @@
   - "./vendor/bin/drush -y"
   not_contains:
   - "--existing-config"
+
+- command: "drupal:site-install"
+  configuration:
+    drupal:
+      site:
+        generate_db_url: false
+  composer: ''
+  contains: []
+  not_contains:
+  - "--db-url='mysql://127.0.0.1:3306'"