diff --git a/manifests/db.pp b/manifests/db.pp
index 69e2081fb..448398e80 100644
--- a/manifests/db.pp
+++ b/manifests/db.pp
@@ -7,7 +7,7 @@
   $collate     = 'utf8_general_ci',
   $host        = 'localhost',
   $grant       = 'ALL',
-  $sql         = '',
+  $sql         = undef,
   $enforce_sql = false,
   $ensure      = 'present'
 ) {