diff --git a/jOOQ/src/main/java/org/jooq/impl/CommitsImpl.java b/jOOQ/src/main/java/org/jooq/impl/CommitsImpl.java
index f47bce9221..b3107a4c00 100644
--- a/jOOQ/src/main/java/org/jooq/impl/CommitsImpl.java
+++ b/jOOQ/src/main/java/org/jooq/impl/CommitsImpl.java
@@ -90,6 +90,9 @@ final class CommitsImpl implements Commits {
 
     @Override
     public void add(Commit commit) {
+        if (root != commit.root())
+            throw new DataMigrationValidationException("A Commits graph must contain a single graph whose commits all share the same root.");
+
         Commit duplicate;
 
         if ((duplicate = commitsById.get(commit.id())) != null)