我不确定使用连接的简单SQL查询有什么问题？-NotcertainwhatiswrongwithmysimpleSQLQueriesthatusejoins?

Unfortunately, I am brand new to SQL and am using SQL Server to create very simple queries, but I am having issues that I am not exactly certain how to work around...

不幸的是，我是SQL的新手，我使用SQL Server创建非常简单的查询，但我遇到的问题我不确定如何解决...

For the first one, I have to comment out the date in order for it to work, otherwise everything is blank...

对于第一个，我必须注释日期才能使它工作，否则一切都是空白的......

SELECT 
    VendorName, InvoiceNumber, InvoiceDate, InvoiceTotal
FROM 
    Vendors 
JOIN 
    Invoices ON Vendors.VendorID = Invoices.VendorID
WHERE 
    InvoiceDate <6/1/2008 
ORDER BY 
    VendorName;

The 2nd one has an extra column that I am not sure how to get rid of.

第二个有一个额外的列，我不知道如何摆脱。

SELECT 
    InvoiceNumber, VendorName, InvoiceDate
FROM 
    Vendors AS v 
JOIN 
    Invoices AS i ON v.VendorID = i.VendorID
WHERE 
    InvoiceTotal > 0; 

And lastly, This one (my other queries work fine) is not working. It is supposed to be joining 3 tables and filtering the results by VendorID sorting by VendorName, then I keep getting this error:

最后，这个（我的其他查询工作正常）不起作用。它应该是加入3个表并按VendorID按VendorName排序过滤结果，然后我不断收到此错误：

Conversion failed when converting the varchar value '115, 122, 123' to data type int.

将varchar值“115,122,123”转换为数据类型int时转换失败。

SELECT 
    InvoiceDate, VendorName, InvoiceNumber, InvoiceLineItemAmount
FROM
    Vendors
JOIN 
    Invoices ON Vendors.VendorID = Invoices.VendorID
JOIN 
    InvoiceLineItems ON Invoices.InvoiceID = InvoiceLineItems.InvoiceID
WHERE 
    Vendors.VendorID = '115, 122, 123'
ORDER BY 
    VendorName;

If anyone can please offer any suggestions, it would be much appreciated, thank you...

如果有人可以提供任何建议，我将不胜感激，谢谢......

2 个解决方案

WHERE InvoiceDate <'6/1/2008' 

Vendors.VendorID IN (115, 122, 123)

WHERE Vendors.VendorID = '115, 122, 123'