Index: lams_common/db/sql/updatescripts/alter_203_transition.sql
===================================================================
diff -u -ra013e19f4975a63a246dbea05b9adda64a274dd1 -r9bd0846dded4812b129fff63625f274ad38c5690
--- lams_common/db/sql/updatescripts/alter_203_transition.sql	(.../alter_203_transition.sql)	(revision a013e19f4975a63a246dbea05b9adda64a274dd1)
+++ lams_common/db/sql/updatescripts/alter_203_transition.sql	(.../alter_203_transition.sql)	(revision 9bd0846dded4812b129fff63625f274ad38c5690)
@@ -1,6 +1,22 @@
 -- Script to be run for LAMS 2.0.3 release, on LAMS 2.0.2 tables.
--- Add a new unique index to the transition table as duplicates cause an error in authoring (LDEV-1229)
+-- Removes existing duplicate rows if they exist
+-- Adds a new unique index to the transition table as duplicates cause an error in authoring (LDEV-1229)
 
+-- Removing duplicate rows
+DELETE bad_rows.* 
+FROM lams_learning_transition as bad_rows
+   INNER JOIN (
+      SELECT MIN(transition_id) AS min_id, to_activity_id, from_activity_id
+      FROM lams_learning_transition
+      GROUP BY  to_activity_id
+      HAVING COUNT(*) > 1
+   ) AS good_rows 
+   	 ON good_rows.to_activity_id = bad_rows.to_activity_id
+     AND good_rows.from_activity_id = bad_rows.from_activity_id
+     AND good_rows.min_id <> bad_rows.transition_id;
+
+
+-- Altering table
 ALTER TABLE lams_learning_transition
 ADD UNIQUE UQ_transition_activities (from_activity_id, to_activity_id);