added querry to check if the state sequenceNumber is already present

utils/init_db.php

@@ -68,7 +68,14 @@ CREATE TABLE IF NOT EXISTS sync_state (
   v VARCHAR(100)
   )
 ");
+
+$result = $conn -> query("SELECT * FROM sync_state WHERE k='sequenceNumber'");
+
+$table_count = $result -> num_rows;
+
+if ($table_count == 0){
 $conn->query("INSERT INTO sync_state (k, v) VALUES ('sequenceNumber', '0');");
+}
 
 echo "Database, users, and tables created successfully.\n";