Index: lams_tool_scratchie/src/java/org/lamsfoundation/lams/tool/scratchie/dbupdates/patch20190510.sql
===================================================================
diff -u
--- lams_tool_scratchie/src/java/org/lamsfoundation/lams/tool/scratchie/dbupdates/patch20190510.sql	(revision 0)
+++ lams_tool_scratchie/src/java/org/lamsfoundation/lams/tool/scratchie/dbupdates/patch20190510.sql	(revision c05bc28426be01ab26818fef24699cea98d568c8)
@@ -0,0 +1,17 @@
+-- Turn off autocommit, so nothing is committed if there is an error
+SET AUTOCOMMIT = 0;
+SET FOREIGN_KEY_CHECKS=0;
+----------------------Put all sql statements below here-------------------------
+
+-- LDEV-4817 Delete existing blank burning questions
+DELETE FROM tl_lascrt11_burning_question WHERE question IS NULL OR TRIM(question) = '';
+
+----------------------Put all sql statements above here-------------------------
+
+-- If there were no errors, commit and restore autocommit to on
+COMMIT;
+SET AUTOCOMMIT = 1;
+SET FOREIGN_KEY_CHECKS=1;
+
+
+
Index: lams_tool_scratchie/src/java/org/lamsfoundation/lams/tool/scratchie/web/controller/LearningController.java
===================================================================
diff -u -r3ee06bc1b00b1673399c1871a73cfa1d8ec2c0db -rc05bc28426be01ab26818fef24699cea98d568c8
--- lams_tool_scratchie/src/java/org/lamsfoundation/lams/tool/scratchie/web/controller/LearningController.java	(.../LearningController.java)	(revision 3ee06bc1b00b1673399c1871a73cfa1d8ec2c0db)
+++ lams_tool_scratchie/src/java/org/lamsfoundation/lams/tool/scratchie/web/controller/LearningController.java	(.../LearningController.java)	(revision c05bc28426be01ab26818fef24699cea98d568c8)
@@ -168,7 +168,7 @@
 	if (isUserLeader) {
 	    Set<Long> answerUids = new HashSet<>();
 	    for (ScratchieItem item : scratchie.getScratchieItems()) {
-		for (ScratchieAnswer answer : (Set<ScratchieAnswer>) item.getAnswers()) {
+		for (ScratchieAnswer answer : item.getAnswers()) {
 		    answerUids.add(answer.getUid());
 		}
 	    }
@@ -627,16 +627,20 @@
 
 	    final String burningQuestion = request
 		    .getParameter(ScratchieConstants.ATTR_BURNING_QUESTION_PREFIX + itemUid);
-	    // update question in sessionMap
-	    item.setBurningQuestion(burningQuestion);
+	    if (StringUtils.isNotBlank(burningQuestion)) {
+		// update question in sessionMap
+		item.setBurningQuestion(burningQuestion);
 
-	    // update new entry
-	    scratchieService.saveBurningQuestion(sessionId, itemUid, burningQuestion);
+		// update new entry
+		scratchieService.saveBurningQuestion(sessionId, itemUid, burningQuestion);
+	    }
 	}
 
 	// handle general burning question
 	final String generalQuestion = request.getParameter(ScratchieConstants.ATTR_GENERAL_BURNING_QUESTION);
-	scratchieService.saveBurningQuestion(sessionId, null, generalQuestion);
+	if (StringUtils.isNotBlank(generalQuestion)) {
+	    scratchieService.saveBurningQuestion(sessionId, null, generalQuestion);
+	}
 	// update general question in sessionMap
 	sessionMap.put(ScratchieConstants.ATTR_GENERAL_BURNING_QUESTION, generalQuestion);
     }