Question

我想在MS Access上创建VIEW定义。我使用了以下CREATE VIEW声明：

SELECT 
   MFP.FollowUpPlan_Id, 
   MFP.FollowUpPlan_Name AS PlanName, 
   DFP.Sequence_No AS SequenceNo, 
   MFS.FollowUpSchedule_Name AS ScheduleName    
FROM 
   MAS_FollowUp_Plan AS MFP, 
   DET_FollowUp_Plan AS DFP, 
   MAS_FollowUp_Schedule AS MFS
WHERE 
   (((MFP.FollowUpPlan_Id)=DFP.FollowUpPlan_Id) AND
   ((DFP.FollowUpSchedule_Id)=MFS.FollowUpSchedule_Id)) AND
   MFP.is_Deleted = FALSE AND
   DFP.is_Deleted = false     
ORDER BY 
   MFP.FollowUpPlan_Id, DFP.Sequence_No;

但它会引发错误：

Only Simple Select Queries are allowed in view.

请提供帮助，提前致谢。

Answer 1

这里的问题，正如Jeroen所解释的，是Access'CREATE VIEW声明的限制。对于这种情况，您可以使用CREATE PROCEDURE代替。它将创建db的QueryDefs集合的新成员---因此，从Access用户界面将显示为新的命名查询。

以下声明适用于我使用VBScript中的ADO。从以前的Delphi问题来看，我的理解是Delphi也可以使用ADO，所以我相信这也适合你。

CREATE PROCEDURE ViewSubstitute AS
SELECT
    MFP.FollowUpPlan_Id,
    MFP.FollowUpPlan_Name AS PlanName,
    DFP.Sequence_No AS SequenceNo,
    MFS.FollowUpSchedule_Name AS ScheduleName
FROM
    (MAS_FollowUp_Plan AS MFP
    INNER JOIN DET_FollowUp_Plan AS DFP
    ON MFP.FollowUpPlan_Id = DFP.FollowUpPlan_Id)
    INNER JOIN MAS_FollowUp_Schedule AS MFS
    ON DFP.FollowUpSchedule_Id = MFS.FollowUpSchedule_Id
WHERE
    MFP.is_Deleted=False AND DFP.is_Deleted=False
ORDER BY
    MFP.FollowUpPlan_Id,
    DFP.Sequence_No;

Answer 2

You cannot mix ORDER BY with JOIN when creating views in Access。它会给你错误"Only simple SELECT queries are allowed in VIEWS."（注意复数VIEWS）

在FROM中拥有多个表格是JOIN的一种表格。

删除ORDER BY，
或FROM中没有JOIN只有一个表。

我记得从过去（当我做了比现在更多的访问时）看到这个用于大型查询的单个表选择也带有ORDER BY。

The consensus is that you should not have ORDER BY in views anyway，这是你最好的事情。

Another reason that you can get the same error message是您添加参数或子选择。 Access也不喜欢视图中的那些，但在您看来并非如此。

Answer 3

在Delphi中声明变量olevarCatalog，cmd为OleVariant，使用ComObj

olevarCatalog := CreateOleObject('ADOX.Catalog');
olevarCatalog.create(YourConnectionString); //This Will create MDB file.
// Using ADO Query(CREATE TABLE TABLEName....) add the required Tables.

// To Insert View Definition on MDB file.
cmd := CreateOleObject('ADODB.Command');
cmd.CommandType := cmdText;
cmd.CommandText := 'ANY Kind of SELECT Query(JOIN, OrderBy is also allowed)';
olevarCatalog.Views.Append('Name of View',cmd);
cmd := null;

这是使用Delphi创建MS ACCESS文件（.MDB）和VIEW的最佳方法。

如何在没有在PC上安装MSAccess的情况下使用Delphi Application在MS Access数据库中创建VIEW？

3 个答案: