diff --git a/CHANGELOG b/CHANGELOG
index a6d40ce..3f9db1b 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -6,6 +6,7 @@
 - Introduced sessions; GUI loads the same relations of the previous time
 - GUI is modified, to be fit smaller screens
 - Fix bug in tokenizer
+- Fixed bug where select on relations with '---' values would always fail
 
 2.0
 - Fix bug in relational-cli that made it crash when an exception was raised
diff --git a/relational/relation.py b/relational/relation.py
index 62595b9..6191713 100644
--- a/relational/relation.py
+++ b/relational/relation.py
@@ -323,7 +323,7 @@ class Relation (object):
                     added = True
             # If it didn't partecipate, adds it
             if not added:
-                item = chain(i, repeat('---', len(noid)))
+                item = chain(i, repeat(rstring('---'), len(noid)))
                 newt.content.add(tuple(item))
 
         return newt
diff --git a/test/select_join.query b/test/select_join.query
new file mode 100644
index 0000000..18692f6
--- /dev/null
+++ b/test/select_join.query
@@ -0,0 +1 @@
+σ id==3(people ⧓ skills)
diff --git a/test/select_join.result b/test/select_join.result
new file mode 100644
index 0000000..51a573d
--- /dev/null
+++ b/test/select_join.result
@@ -0,0 +1,2 @@
+id,skill,name,chief,age
+3,C++,dean,1,33