code: private static void appendCondition(DbMapping dbMapping, StringBuilder sql, Map<String, Object> values,
                                          ResultSet rs) throws SQLException {
          // 拼接主键
          for (Map.Entry<String, String> entry : dbMapping.getTargetPk().entrySet()) {
              String targetColumnName = entry.getKey();
              String srcColumnName = entry.getValue();
              if (srcColumnName == null) {
                  srcColumnName = targetColumnName;
              }
              sql.append(targetColumnName).append("=? AND ");
              values.put(targetColumnName, rs.getObject(srcColumnName));
          }
          int len = sql.length();
          sql.delete(len - 4, len);
      }
docs: 拼接目标表主键where条件