首页 > 解决方案 > 在 oracle SQL 中正确排序分页结果

问题描述

我有一个数据表服务器端分页的实现。查询生成器如下所示:

public static String buildPaginatedQueryForOracle(String baseQuery, PaginationCriteria paginationCriteria) {

        StringBuilder sb = new StringBuilder(
                "SELECT * FROM (SELECT FILTERED_ORDERED_RESULTS.*, COUNT(1) OVER() total_records, ROWNUM AS RN FROM (SELECT BASEINFO.* FROM ( #BASE_QUERY# ) BASEINFO ) FILTERED_ORDERED_RESULTS #WHERE_CLAUSE# #ORDER_CLASUE# ) WHERE RN > (#PAGE_NUMBER# * #PAGE_SIZE#) AND RN <= (#PAGE_NUMBER# + 1) * #PAGE_SIZE# ");
        String finalQuery = null;

        int pageNo = paginationCriteria.getPageNumber() / paginationCriteria.getPageSize();
        paginationCriteria.setPageNumber(pageNo);

        if (!AppUtil.isObjectEmpty(paginationCriteria)) {
            finalQuery = sb.toString().replaceAll("#BASE_QUERY#", baseQuery)
                    .replaceAll("#WHERE_CLAUSE#",
                            ((AppUtil.isObjectEmpty(paginationCriteria.getFilterByClause())) ? "" : " WHERE ")
                                    + paginationCriteria.getFilterByClause())
                    .replaceAll("#ORDER_CLASUE#", paginationCriteria.getOrderByClause())
                    .replaceAll("#PAGE_NUMBER#", paginationCriteria.getPageNumber().toString())
                    .replaceAll("#PAGE_SIZE#", paginationCriteria.getPageSize().toString());
        }
        return (null == finalQuery) ? baseQuery : finalQuery;
    }

其中 base_query 是来自 dao-impl 层的常用字符串。它做得很好。但是,当我想在 order 子句中按 cnt 对结果进行排序时(这种特殊情况使用 cnt 来计算链接到第一个表中每一行的另一个表的行,如下所示)

SELECT *
  FROM (
       SELECT FILTERED_ORDERED_RESULTS.*,
              COUNT(1) OVER() TOTAL_RECORDS
         FROM (
              SELECT BASEINFO.*,
                     ROWNUM AS RN
                FROM (
                     SELECT A.ID_LIST            AS ID,
                            A.NAME,
                            A.DATE_CREATE        AS DATECREATE,
                            A.DATE_UPDATE        AS DATEUPDATE,
                            A.USER_ID            AS USERID,
                            A.TYPE,
                            NVL(
                                   B.CNT, 0
                            )        CNT
                       FROM MAP_S_LIST_ARTS                                                           A
                       LEFT JOIN (
                            SELECT ID_LIST,
                                   COUNT(*) CNT
                              FROM MAP_LIST_ARTS
                             GROUP BY ID_LIST
                     )        B ON A.ID_LIST = B.ID_LIST
                      ORDER BY A.ID_LIST DESC
              ) BASEINFO
       ) FILTERED_ORDERED_RESULTS
        ORDER BY CNT DESC
)
 WHERE RN > (:PAGE * 5) AND RN <= (:PAGE + 1) * 5 

我得到的是它首先在另一个排序中采用前 5 行(默认是按 id),然后仅将按 cnt 的排序应用于它们。例如,如果我获取一个有 5 行的页面,它只会在其中排序,尽管我还有其他页面。我能做些什么?

标签: javasqloracleoracle10g

解决方案


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