Update mysql-db-wrapper.js

lib/db/mysql-db-wrapper.js

@@ -1430,7 +1430,7 @@ class MySqlDbWrapper {
 
     const params = [txs.map(tx => [
       tx.txid,
-      tx.created,
+      tx.created ? tx.created : until.unix(),
       tx.version,
       tx.locktime
     ])]