diff --git a/database/conference.go b/database/conference.go
index 1b93e2a..7efb64f 100644
--- a/database/conference.go
+++ b/database/conference.go
@@ -580,7 +580,7 @@ func (c *Conference) UnreadMessages(ctx context.Context, u *User) (int32, error)
 		return 0, nil
 	}
 	var rc int32
-	err = amdb.GetContext(ctx, &rc, `SELECT SUM(t.top_message - IFNULL(s.last_message,-1))
+	err = amdb.GetContext(ctx, &rc, `SELECT SUM(t.top_message - COALESCE(s.last_message,-1))
 		FROM topics t LEFT JOIN topicsettings s ON t.topicid = s.topicid AND s.uid = ?
 		WHERE t.confid = ? AND t.archived = 0 AND (s.hidden IS NULL OR s.hidden = 0)`, u.Uid, c.ConfId)
 	return rc, err
@@ -800,7 +800,7 @@ func (c *Conference) GetActiveUserEMailAddrs(ctx context.Context, userSelect, da
 
 // Stats retrieves the number of topics and posts in this conference.
 func (c *Conference) Stats(ctx context.Context) (int, int, error) {
-	row := amdb.QueryRowContext(ctx, "SELECT COUNT(*), SUM(top_message + 1) FROM topics WHERE confid = ?", c.ConfId)
+	row := amdb.QueryRowContext(ctx, "SELECT COUNT(*), COALESCE(SUM(top_message + 1), 0) FROM topics WHERE confid = ?", c.ConfId)
 	ntopic := 0
 	npost := 0
 	err := row.Scan(&ntopic, &npost)
diff --git a/database/post.go b/database/post.go
index 0c28cf8..8b8c27d 100644
--- a/database/post.go
+++ b/database/post.go
@@ -800,7 +800,7 @@ func AmSearchPosts(ctx context.Context, searchTerms string, u *User, offset, max
 			JOIN commmember m ON m.commid = q.commid JOIN users u ON u.uid = m.uid JOIN commftrs f ON f.commid = q.commid
 			JOIN topics t ON t.confid = c.confid JOIN posts p ON p.topicid = t.topicid JOIN postdata d ON d.postid = p.postid JOIN users u2 ON u2.uid = p.creator_uid
 			LEFT JOIN confmember x ON (c.confid = x.confid AND u.uid = x.uid)
-			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,IFNULL(x.granted_lvl,0)) >= c.read_lvl
+			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,COALESCE(x.granted_lvl,0)) >= c.read_lvl
 			AND p.scribble_uid IS NULL AND MATCH(d.data) AGAINST (?)`, u.Uid, confService, searchTerms)
 	case "community":
 		err = amdb.GetContext(ctx, &count, `SELECT COUNT(*)
@@ -808,7 +808,7 @@ func AmSearchPosts(ctx context.Context, searchTerms string, u *User, offset, max
 			JOIN commmember m ON m.commid = q.commid JOIN users u ON u.uid = m.uid JOIN commftrs f ON f.commid = q.commid
 			JOIN topics t ON t.confid = c.confid JOIN posts p ON p.topicid = t.topicid JOIN postdata d ON d.postid = p.postid JOIN users u2 ON u2.uid = p.creator_uid
 			LEFT JOIN confmember x ON (c.confid = x.confid AND u.uid = x.uid)
-			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,IFNULL(x.granted_lvl,0)) >= c.read_lvl
+			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,COALESCE(x.granted_lvl,0)) >= c.read_lvl
 			AND q.commid = ? AND p.scribble_uid IS NULL AND MATCH(d.data) AGAINST (?)`, u.Uid, confService, comm.Id, searchTerms)
 	case "conference":
 		err = amdb.GetContext(ctx, &count, `SELECT COUNT(*)
@@ -816,7 +816,7 @@ func AmSearchPosts(ctx context.Context, searchTerms string, u *User, offset, max
 			JOIN commmember m ON m.commid = q.commid JOIN users u ON u.uid = m.uid JOIN commftrs f ON f.commid = q.commid
 			JOIN topics t ON t.confid = c.confid JOIN posts p ON p.topicid = t.topicid JOIN postdata d ON d.postid = p.postid JOIN users u2 ON u2.uid = p.creator_uid
 			LEFT JOIN confmember x ON (c.confid = x.confid AND u.uid = x.uid)
-			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,IFNULL(x.granted_lvl,0)) >= c.read_lvl
+			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,COALESCE(x.granted_lvl,0)) >= c.read_lvl
 			AND q.commid = ? AND c.confid = ? AND p.scribble_uid IS NULL AND MATCH(d.data) AGAINST (?)`, u.Uid, confService, comm.Id, conf.ConfId, searchTerms)
 	case "topic":
 		err = amdb.GetContext(ctx, &count, `SELECT COUNT(*)
@@ -824,7 +824,7 @@ func AmSearchPosts(ctx context.Context, searchTerms string, u *User, offset, max
 			JOIN commmember m ON m.commid = q.commid JOIN users u ON u.uid = m.uid JOIN commftrs f ON f.commid = q.commid
 			JOIN topics t ON t.confid = c.confid JOIN posts p ON p.topicid = t.topicid JOIN postdata d ON d.postid = p.postid JOIN users u2 ON u2.uid = p.creator_uid
 			LEFT JOIN confmember x ON (c.confid = x.confid AND u.uid = x.uid)
-			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,IFNULL(x.granted_lvl,0)) >= c.read_lvl
+			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,COALESCE(x.granted_lvl,0)) >= c.read_lvl
 			AND q.commid = ? AND c.confid = ? AND t.topicid = ? AND p.scribble_uid IS NULL AND MATCH(d.data) AGAINST (?)`,
 			u.Uid, confService, comm.Id, conf.ConfId, topic.TopicId, searchTerms)
 	}
@@ -842,7 +842,7 @@ func AmSearchPosts(ctx context.Context, searchTerms string, u *User, offset, max
 			JOIN commmember m ON m.commid = q.commid JOIN users u ON u.uid = m.uid JOIN commftrs f ON f.commid = q.commid
 			JOIN topics t ON t.confid = c.confid JOIN posts p ON p.topicid = t.topicid JOIN postdata d ON d.postid = p.postid JOIN users u2 ON u2.uid = p.creator_uid
 			LEFT JOIN confmember x ON (c.confid = x.confid AND u.uid = x.uid)
-			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,IFNULL(x.granted_lvl,0)) >= c.read_lvl
+			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,COALESCE(x.granted_lvl,0)) >= c.read_lvl
 			AND p.scribble_uid IS NULL AND MATCH(d.data) AGAINST (?) ORDER BY q.commname, c.name, t.num, p.num
 			LIMIT ? OFFSET ?`, u.Uid, confService, searchTerms, max, offset)
 	case "community":
@@ -851,7 +851,7 @@ func AmSearchPosts(ctx context.Context, searchTerms string, u *User, offset, max
 			JOIN commmember m ON m.commid = q.commid JOIN users u ON u.uid = m.uid JOIN commftrs f ON f.commid = q.commid
 			JOIN topics t ON t.confid = c.confid JOIN posts p ON p.topicid = t.topicid JOIN postdata d ON d.postid = p.postid JOIN users u2 ON u2.uid = p.creator_uid
 			LEFT JOIN confmember x ON (c.confid = x.confid AND u.uid = x.uid)
-			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,IFNULL(x.granted_lvl,0)) >= c.read_lvl
+			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,COALESCE(x.granted_lvl,0)) >= c.read_lvl
 			AND q.commid = ? AND p.scribble_uid IS NULL AND MATCH(d.data) AGAINST (?) ORDER BY q.commname, c.name, t.num, p.num
 			LIMIT ? OFFSET ?`, u.Uid, confService, comm.Id, searchTerms, max, offset)
 	case "conference":
@@ -860,7 +860,7 @@ func AmSearchPosts(ctx context.Context, searchTerms string, u *User, offset, max
 			JOIN commmember m ON m.commid = q.commid JOIN users u ON u.uid = m.uid JOIN commftrs f ON f.commid = q.commid
 			JOIN topics t ON t.confid = c.confid JOIN posts p ON p.topicid = t.topicid JOIN postdata d ON d.postid = p.postid JOIN users u2 ON u2.uid = p.creator_uid
 			LEFT JOIN confmember x ON (c.confid = x.confid AND u.uid = x.uid)
-			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,IFNULL(x.granted_lvl,0)) >= c.read_lvl
+			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,COALESCE(x.granted_lvl,0)) >= c.read_lvl
 			AND q.commid = ? AND c.confid = ? AND p.scribble_uid IS NULL AND MATCH(d.data) AGAINST (?) ORDER BY q.commname, c.name, t.num, p.num
 			LIMIT ? OFFSET ?`, u.Uid, confService, comm.Id, conf.ConfId, searchTerms, max, offset)
 	case "topic":
@@ -869,7 +869,7 @@ func AmSearchPosts(ctx context.Context, searchTerms string, u *User, offset, max
 			JOIN commmember m ON m.commid = q.commid JOIN users u ON u.uid = m.uid JOIN commftrs f ON f.commid = q.commid
 			JOIN topics t ON t.confid = c.confid JOIN posts p ON p.topicid = t.topicid JOIN postdata d ON d.postid = p.postid JOIN users u2 ON u2.uid = p.creator_uid
 			LEFT JOIN confmember x ON (c.confid = x.confid AND u.uid = x.uid)
-			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,IFNULL(x.granted_lvl,0)) >= c.read_lvl
+			WHERE u.uid = ? AND f.ftr_code = ? AND GREATEST(u.base_lvl,m.granted_lvl,s.granted_lvl,COALESCE(x.granted_lvl,0)) >= c.read_lvl
 			AND q.commid = ? AND c.confid = ? AND t.topicid = ? AND p.scribble_uid IS NULL AND MATCH(d.data) AGAINST (?) ORDER BY q.commname, c.name, t.num, p.num
 			LIMIT ? OFFSET ?`, u.Uid, confService, comm.Id, conf.ConfId, topic.TopicId, searchTerms, max, offset)
 	}
diff --git a/database/topic.go b/database/topic.go
index 2623629..2ec7d69 100644
--- a/database/topic.go
+++ b/database/topic.go
@@ -610,7 +610,7 @@ func AmListTopics(ctx context.Context, confid int32, uid int32, viewOption int,
 	case TopicViewAll:
 		whereClause = ""
 	case TopicViewNew:
-		tail := "t.top_message > IFNULL(s.last_message,-1)"
+		tail := "t.top_message > COALESCE(s.last_message,-1)"
 		if !ignoreSticky {
 			tail = "(t.sticky = 1 OR " + tail + ")"
 		}
@@ -673,9 +673,9 @@ func AmListTopics(ctx context.Context, confid int32, uid int32, viewOption int,
 
 	// Build the full SQL statement
 	var fullStatement strings.Builder
-	fullStatement.WriteString("SELECT t.topicid, t.num, t.name, (t.top_message - IFNULL(s.last_message,-1)) AS unread, ")
-	fullStatement.WriteString("(t.top_message + 1) AS total, t.lastupdate, t.frozen, t.archived, IFNULL(s.subscribe,0) AS subscribe, ")
-	fullStatement.WriteString("IFNULL(s.hidden,0) AS hidden, t.sticky, GREATEST(SIGN(t.top_message - IFNULL(s.last_message,-1)),0) AS newflag ")
+	fullStatement.WriteString("SELECT t.topicid, t.num, t.name, (t.top_message - COALESCE(s.last_message,-1)) AS unread, ")
+	fullStatement.WriteString("(t.top_message + 1) AS total, t.lastupdate, t.frozen, t.archived, COALESCE(s.subscribe,0) AS subscribe, ")
+	fullStatement.WriteString("COALESCE(s.hidden,0) AS hidden, t.sticky, GREATEST(SIGN(t.top_message - COALESCE(s.last_message,-1)),0) AS newflag ")
 	fullStatement.WriteString("FROM topics t LEFT JOIN topicsettings s ON t.topicid = s.topicid AND s.uid = ? WHERE t.confid = ? ")
 	if whereClause != "" {
 		fullStatement.WriteString("AND ")