使用 ROW_NUMBER 应用分页

Question

我有下面的java方法，用于使用本机查询从Oracle数据库获取数据，并且它在查询中有多个UNION，现在我想在ROW_NUMBER和偏移量的帮助下应用分页。 下面是我的java方法：

public PagingResult fetch(PatDocumentSearchCriteria searchCriteria, Long practice, Long patient) {
        final StringBuilder queryString = new StringBuilder();

        queryString.append("WITH applicable_pat_documents AS (");
        queryString.append("    SELECT * FROM");
        queryString.append("        ( SELECT");
        queryString.append("            pd.id id");
        queryString.append("        FROM");
        queryString.append("            pat_document pd");

        if (!CollectionUtils.isEmpty(searchCriteria.getDocumentTypes())) {
            queryString.append(" LEFT OUTER JOIN pat_document_type_def pdtd ON pd.patdocumenttypedef = pdtd.id ");
        }

        queryString.append("        WHERE");
        queryString.append("            pd.practice = :" + QueryParams.PRACTICE_ID);
        queryString.append("            AND pd.patient = :" + QueryParams.PATIENT_ID);
        queryString.append("            AND pd.purgetype IS NULL");
        queryString.append("            AND pd.reviewstatus IN ( 'REVIEWED', 'PENDING', 'NOT_REQUIRED' )");
        queryString.append("            AND pd.draft = 0");
        queryString.append("            AND pd.deleted = 0");
        queryString.append("            AND (pd.patdocumentinternaltype in ('ClinicalNote', 'G1Attachment') OR exists (select 1 from PAT_DOCUMENT_ENTITY_REF pder where pder.PATDOCUMENT = pd.id))");
        queryString.append("            AND NOT EXISTS (SELECT 1 from pat_result_attachment pra where pra.patdocument = pd.id)");

        if (!CollectionUtils.isEmpty(searchCriteria.getDocumentTypes())) {
            queryString.append("      AND ").append(DBUtils.generateNativeQueryInClause("PDTD.NAME", DOCUMENT_TYPE,
                    searchCriteria.getDocumentTypes().size()));
        }

        queryString.append("        ORDER BY");
        queryString.append("            pd.dateofservice DESC,");
        queryString.append("            pd.modifieddate DESC");
        queryString.append("    )");
        queryString.append(")");

        queryString.append(" SELECT");
        queryString.append("    pd.id           id,");
        queryString.append("    DECODE(PD.PATDOCUMENTINTERNALTYPE");
        queryString.append("        , 'ClinicalNote', PD.DOCUMENTNAME");
        queryString.append("        , 'NurseNote', 'Nurse Note'");
        queryString.append("        , PDTD.NAME) ");
        queryString.append("            || DECODE(PD.patdocumentamendedstatus, 'Amended' , ' (Amended)', 'Replaced', ' (Replaced)')");
        queryString.append("            || DECODE(cna.id,  null, '', ' (Addendum)' ) name,");
        queryString.append("    pdtd.name       documenttype,");
        queryString.append("    pd.dateOfService dateOfService,");
        queryString.append("    trim(DECODE(PD.PATDOCUMENTINTERNALTYPE, '" + PatDocumentInternalType.ClinicalNote.name() + "', PKG_UTIL.PROVIDERNAME(UOW.ID) ,");
        queryString.append("            '" + PatDocumentInternalType.NurseNote.name() + "' , pkg_orders.generateFullUserName(pd.ownerUser,2))) author, ");
        queryString.append("    DECODE(PD.PATDOCUMENTINTERNALTYPE, '" + PatDocumentInternalType.ClinicalNote.name() + "', UOW.ID,");
        queryString.append("            '" + PatDocumentInternalType.NurseNote.name() + "' , pd.ownerUser) authorId, ");
        queryString.append("    pd.createddate  createddate,");
        queryString.append("    pd.modifieddate modifieddate,");
        queryString.append("    '").append(PatDocumentMetaDataDTO.EntityType.PatDocument).append("' entityType");
        queryString.append(" FROM");
        queryString.append("    applicable_pat_documents pr");
        queryString.append("    JOIN pat_document pd ON pr.id = pd.id");
        queryString.append("    LEFT OUTER JOIN PAT_DOCUMENT_TYPE_DEF PDTD ON PD.PATDOCUMENTTYPEDEF = PDTD.ID");
        queryString.append("    LEFT OUTER JOIN USERS UOW ON PD.OWNERUSER = UOW.ID ");
        queryString.append("    LEFT OUTER JOIN CLINICAL_NOTE_ADDENDUM cna on cna.patdocument = pd.id ");

        queryString.append(" UNION");

        queryString.append(" SELECT");
        queryString.append("    id,");
        queryString.append("    name,");
        queryString.append("    NVL(documenttype,'").append(RESULTS_DOCUMENT_TYPE).append("') as documenttype,");
        queryString.append("    reportDate dateofservice,");
        queryString.append("    null author,");
        queryString.append("    null authorId,");
        queryString.append("    createddate,");
        queryString.append("    modifieddate,");
        queryString.append("    '").append(PatDocumentMetaDataDTO.EntityType.PatResultAttachment).append("' entityType");
        queryString.append(" FROM");
        queryString.append("    (");
        queryString.append("    SELECT DISTINCT");
        queryString.append("        pra.id id,");
        queryString.append("        prh.reportDate,");
        queryString.append("        fa.createdDate,");
        queryString.append("        fa.modifieddate modifieddate,");
        queryString.append("        pra.documentname name,");
        queryString.append("        pdtd.name documenttype");
        queryString.append("    FROM");
        queryString.append("        pat_result_attachment pra");
        queryString.append("        left join pat_document pd on pd.id = pra.patdocument");
        queryString.append("        LEFT JOIN pat_document_type_def  pdtd ON pd.patdocumenttypedef = pdtd.id");
        queryString.append("        INNER JOIN file_attachment fa ON fa.id = pra.fileattachment");
        queryString.append("        INNER JOIN pat_result_header prh on prh.id = pra.patresultheader");
        queryString.append("    WHERE");
        queryString.append("        pra.practice = :" + QueryParams.PRACTICE_ID);
        queryString.append("        and pra.patient = :" + QueryParams.PATIENT_ID);
        queryString.append("        and prh.INTERFACEMESSAGEUID is null");
        queryString.append("    )");

        queryString.append(" UNION");

        queryString.append(" SELECT");
        queryString.append("    id,");
        queryString.append("    conceptname as name,");
        queryString.append("    '").append(RESULTS_DOCUMENT_TYPE).append("' documenttype,");
        queryString.append("    reportDate  as dateofservice,");
        queryString.append("    null author,");
        queryString.append("    null authorId,");
        queryString.append("    createddate,");
        queryString.append("    modifieddate,");
        queryString.append("    '").append(PatDocumentMetaDataDTO.EntityType.PatMolecularResult).append("' entityType");
        queryString.append(" FROM ");
        queryString.append("        pat_result_header prh");
        queryString.append("    WHERE");
        queryString.append("        prh.practice = :" + QueryParams.PRACTICE_ID);
        queryString.append("        and prh.patient = :" + QueryParams.PATIENT_ID);
        queryString.append("        and prh.INTERFACEMESSAGEUID is not null");

        Query query = entityManager.createNativeQuery(queryString.toString())
                .setParameter(QueryParams.PRACTICE_ID, practice)
                .setParameter(QueryParams.PATIENT_ID, patient);

        if (!CollectionUtils.isEmpty(searchCriteria.getDocumentTypes())) {
            String queryVariable;
            for (int i = 0; i < searchCriteria.getDocumentTypes().size(); i++) {
                queryVariable = DOCUMENT_TYPE + i;
                query.setParameter(queryVariable, searchCriteria.getDocumentTypes().get(i));
            }
        }

        List<PatDocumentMetaDataDTO> results = DBUtils.generateList(query, PatDocumentMetaDataDTO.class,
                new PatDocumentMetaDataDTO().propertyNames());

        PagingResult<PatDocumentMetaDataDTO> result = new PagingResult<>();
        result.setResults(results);
        result.setTotalResultCount(results.isEmpty() ? 0 : results.size());

        return result;
    }

尝试应用此 ROW_NUMBER 和偏移量概念，但似乎不起作用。

Answer 1

如果您想修改查询以枚举行，然后根据行号范围进行过滤，则可以使用：

WITH applicable_pat_documents AS (
  ...
),
your_union_query (
  ...
),
apply_row_number(
  SELECT q.*,
         ROW_NUMBER() OVER (ORDER BY something) AS rn
  FROM   your_union_query q
)
SELECT *
FROM   apply_row_number
WHERE  rn BETWEEN min_rn AND max_rn;