code: public int update() {
          this.beforeCheck();
          String       sql             = this.buildUpdateSQL(null, updateColumns);
          List<Object> columnValueList = new ArrayList<>();
          updateColumns.forEach((key, value) -> columnValueList.add(value));
          columnValueList.addAll(paramValues);
          return this.execute(sql, columnValueList);
      }
docs: Update operation
  
  @return affect the number of rows