diff --git a/modules/store/src/main/scala/docspell/store/impl/Column.scala b/modules/store/src/main/scala/docspell/store/impl/Column.scala
index 2357664b..87253163 100644
--- a/modules/store/src/main/scala/docspell/store/impl/Column.scala
+++ b/modules/store/src/main/scala/docspell/store/impl/Column.scala
@@ -32,7 +32,7 @@ case class Column(name: String, ns: String = "", alias: String = "") {
   def is[A: Put](ov: Option[A]): Fragment =
     ov match {
       case Some(v) => f ++ fr" = $v"
-      case None    => fr"is null"
+      case None    => f ++ fr"is null"
     }
 
   def is(c: Column): Fragment =