diff --git a/src/db/mod.rs b/src/db/mod.rs
index 288c7a40..ee66f4b8 100644
--- a/src/db/mod.rs
+++ b/src/db/mod.rs
@@ -106,6 +106,7 @@ fn upgrade(db: &Connection, mut version: u16) -> Result<(), Error> {
     apply_sql!(db, version, 1, "schema1.sql");
     apply_sql!(db, version, 2, "schema2.sql");
     apply_sql!(db, version, 3, "schema3.sql");
+    apply_sql!(db, version, 4, "schema4.sql");
     info!("Database is at version {}", version);
 
     Ok(())
diff --git a/src/db/schema4.sql b/src/db/schema4.sql
new file mode 100644
index 00000000..1dce5020
--- /dev/null
+++ b/src/db/schema4.sql
@@ -0,0 +1,23 @@
+
+ALTER TABLE relay ADD COLUMN last_success_at INTEGER DEFAULT NULL;
+
+PRAGMA foreign_keys=off;
+BEGIN TRANSACTION;
+ALTER TABLE event_tag RENAME TO event_tag_old;
+CREATE TABLE event_tag (
+    event TEXT NOT NULL,
+    seq INTEGER NOT NULL,
+    label TEXT DEFAULT NULL,
+    field0 TEXT DEFAULT NULL,
+    field1 TEXT DEFAULT NULL,
+    field2 TEXT DEFAULT NULL,
+    field3 TEXT DEFAULT NULL,
+    UNIQUE (event, seq),
+    CONSTRAINT fk_event
+      FOREIGN KEY (event) REFERENCES event (id)
+      ON DELETE CASCADE
+);
+INSERT INTO event_tag SELECT * FROM event_tag_old;
+COMMIT;
+PRAGMA foreign_keys=on;
+DROP TABLE event_tag_old;