如何在子查询 SQL Server 中使用 Left Join？

Question

I am trying to use left join in subquery in SQL Server. My query looks fine to me but it gives syntax error.

This is my query:

(
SELECT 
    FK_OrderNo AS LHNo, VendorName AS LHVendor
FROM 
    tbl_ShipmentAPAR 
LEFT JOIN
    tbl_vendors ON FK_VendorID = VendorID
WHERE
    FK_ServiceID = 'LH'
) LHBase ON PK_OrderNo = LHNo 
LEFT JOIN 
    (SELECT
         FK_OrderNo AS DANo,
         VendorName AS DAVendor
     FROM 
         tbl_ShipmentAPAR 
     LEFT JOIN 
         tbl_vendors ON FK_VendorId = VendorId
     WHERE 
         FK_ServiceId = 'DA') DABase ON PK_OrderNo = DANo

This is the error I'm getting:

This is my table structure:

CREATE TABLE tbl_ShipmentAPAR 
(
     VendorID int PRIMARY KEY,
     VendorName varchar(200), 
     FK_OrderNo int 
)

CREATE TABLE tbl_vendors
(
     FK_VendorID int, 
     FOREIGN KEY (FK_VendorID) REFERENCES tbl_ShipmentAPAR(VendorID), 
     FK_ServiceID varchar(200)
)

INSERT INTO tbl_ShipmentAPAR VALUES (1, 'John',123)
INSERT INTO tbl_vendors VALUES (1,'LH')

Answer 1

As @Chris mentioned, the query is bit incomplete. I guess you are trying to do something like this:

SELECT * FROM    /*--> Added new */
(
SELECT 
    FK_OrderNo AS LHNo, VendorName AS LHVendor
FROM 
    tbl_ShipmentAPAR
LEFT JOIN
    tbl_vendors ON FK_VendorID = VendorID
WHERE
    FK_ServiceID = 'LH'
) LHBase
LEFT JOIN 
    (SELECT
         FK_OrderNo AS DANo,
         VendorName AS DAVendor
     FROM 
         tbl_ShipmentAPAR 
     LEFT JOIN 
         tbl_vendors ON FK_VendorId = VendorId
     WHERE 
         FK_ServiceId = 'DA') DABase ON LHBase.LHNo = DABase.DANo /* -->Modified PKOrder no to LHNo because PKOrder no doesn't exist in either of the sub-queries */

This query worked for me. Comment to this answer if something must be changed.