Question

我有两张表和列纸，没有关于那篇论文的一些数据。我正在尝试根据纸张编号搜索所有数据。从两个表中。我已成功编写了查询，并且正在成功检索数据。但我注意到了。如果我的paperNo包含零（0），则查询不会搜索该数据。而对于非零包含纸张，它两次检索相同的记录。

我不明白出了什么问题。尝试了一切。

这是我的查询.-

SELECT PaperDate.paperNo,
       PaperDate.RAW_PAPER,
       PaperDate.EDGE_SEALED,
       PaperDate.HYDRO_120,
       PaperDate.HYDRO_350,
       PaperDate.CATALYST_1ST,
       PaperDate.CATALYST_2ND,
       PaperDate.SIC_350,
       tblThicknessPaperDate.rawThickness,
       tblThicknessPaperDate.catThickness,
       tblThicknessPaperDate.sicThickness,
       tblThicknessPaperDate.rejectedThickness
FROM tblThicknessPaperDate
FULL OUTER JOIN PaperDate ON PaperDate.paperNo =tblThicknessPaperDate.paperNo
WHERE (tblThicknessPaperDate.paperNo = @paperNo)

Answer 1

我会尝试：

FROM tblThicknessPaperDate
RIGHT JOIN PaperDate ON PaperDate.paperNo =tblThicknessPaperDate.paperNo
WHERE (PaperDate.paperNo = @paperNo)

这两个变化是：交换到右连接，所以即使记录不在tblThicknessPaperDate中，我们仍然会在PaperDate中看到记录。另一个变化是在where子句中使用PapterDate.paperNo。由于tblThicknessPaperDate.paperNo可能为null，因此我们不希望在可以避免的地方使用它。

Answer 2

SELECT PaperDate.paperNo,
       PaperDate.RAW_PAPER,
       PaperDate.EDGE_SEALED,
       PaperDate.HYDRO_120,
       PaperDate.HYDRO_350,
       PaperDate.CATALYST_1ST,
       PaperDate.CATALYST_2ND,
       PaperDate.SIC_350,
       tblThicknessPaperDate.rawThickness,
       tblThicknessPaperDate.catThickness,
       tblThicknessPaperDate.sicThickness,
       tblThicknessPaperDate.rejectedThickness
FROM tblThicknessPaperDate
FULL OUTER JOIN PaperDate ON PaperDate.paperNo =tblThicknessPaperDate.paperNo
WHERE (tblThicknessPaperDate.paperNo = @papNo | PaperDate.paperNo = @paperNo)

如果记录包含零，则SQL Query不搜索数据

2 个答案: