带案例条件的JPA查询

Question

(Case a.statusCd When 'ln' then 'loan' else a.status_cd end) as statusCd

为什么这个jpa查询会返回错误？

整个查询字符串是

String qryString = "select"
                + " a.biblioId, " // 0
                + " a.copyId, " // 1
                + " a.copyDescr, "// 2
                + " a.employeeId, "// 3
                + " (Case a.statusCd When 'ln' then 'loan' else a.status_cd end) as statusCd, "// 4
                + " a.statusBeginDt, "// 5
                + " a.libListingCopyId, "// 6
                + " a.barcodeNbr, " // 7
                + " b.title, " // 8
                + " b.author " // 9
                + " from LibListingCopy a, LibListing b " + " where  "
                + curStmt + "and " + authStmt
                + "and a.biblioId = b.biblioId and a.siteId=b.siteId and "
                + bibStmt + " and  " + cpyStmt + " and " + libCodeStmt
                + " and " + accnNbrStmt;

Answer 1

请检查您的查询，我认为同一个字段有两个单独的字段名：

(Case a.statusCd When 'ln' then 'loan' else a.status_cd end) as statusCd

应该是

(Case a.statusCd When 'ln' then 'loan' else a.statusCd end) as statusCd

或（对于另一种可能性）

(Case a.status_cd When 'ln' then 'loan' else a.status_cd end) as statusCd

所以失败可能是你的领域的拼写 a.status_cd / a.statusCd