code: public static Record findById(String tableName, Object idValue) {
  		return MAIN.findById(tableName, idValue);
  	}
docs: Find record by id with default primary key.
  <pre>
  Example:
  Record user = Db.findById("user", 15);
  </pre>
  @param tableName the table name of the table
  @param idValue the id value of the record