From 6baa2a2f5ef5b11859b95f453338efaf7c5b2724 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <e.dolstra@tudelft.nl>
Date: Wed, 24 Feb 2010 14:39:52 +0000
Subject: [PATCH]

---
 src/libstore/schema.sql | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/libstore/schema.sql b/src/libstore/schema.sql
index 4adad34b7..7438632ed 100644
--- a/src/libstore/schema.sql
+++ b/src/libstore/schema.sql
@@ -22,7 +22,7 @@ create index if not exists IndexReference on Refs(reference);
 -- ValidPaths to cause a foreign key constraint violation (due to `on
 -- delete restrict' on the `reference' column).  Therefore, explicitly
 -- get rid of self-references.
-create trigger DeleteSelfRefs before delete on ValidPaths
+create trigger if not exists DeleteSelfRefs before delete on ValidPaths
   begin
     delete from Refs where referrer = old.id and reference = old.id;
   end;