diff --git a/src/Database/Migration/SQLGenerator.php b/src/Database/Migration/SQLGenerator.php
index 4b8d1efa..0aee27ac 100644
--- a/src/Database/Migration/SQLGenerator.php
+++ b/src/Database/Migration/SQLGenerator.php
@@ -343,7 +343,10 @@ private function composeAddColumn(string $name, array $description): string
         }
 
         // Add default value
-        if ($default) {
+        if (!is_null($default)) {
+            if (is_bool($default)) {
+                $default = $default ? 'true' : 'false';
+            }
             $type = sprintf('%s DEFAULT %s', $type, $default);
         }