creating indexing for SQL tunning

1. Not so long time ago, I got a report from customer. It's reported that they had a report getted very slow and finally throw an error. I finded fout the problem sql in source code and excuted it in sql managment studio. It costs 1 minute and 46 seconds to run this sql. Indeed, it's quite slowly.

orginal sql:

SELECT distinct case when tblShopPayment.AccountID=0 then 1 else 0 end as Category, tblShopPayment.PaymentID, tblShopPayment.OperatorID, tblShopPayment.AccountID,
tblShopPayment.PaymentCreateDate, tblShopPayment.PaymentModeID, tblShopPayment.FlagPaid, tblShopPaymentDetail.ProductName, tblShopPaymentDetail.Quantity, tblShopPaymentDetail.Price,
vw_ShopAccountInfo.FirstName, vw_ShopAccountInfo.LastName, tblShopPaymentMode.PaymentModeName FROM tblShopPaymentMode INNER JOIN tblShopPayment INNER JOIN tblShopPaymentDetail
ON tblShopPayment.PaymentID = tblShopPaymentDetail.PaymentID ON tblShopPaymentMode.PaymentModeID = tblShopPayment.PaymentModeID INNER JOIN TblShopProduct
ON tblShopPaymentDetail.ProductID = TblShopProduct.ProductID INNER JOIN tblShopProductCategory ON TblShopProduct.CategoryID = tblShopProductCategory.ProductCategoryID
LEFT OUTER JOIN vw_ShopAccountInfo INNER JOIN tblShopAccount ON vw_ShopAccountInfo.UniqueNo = tblShopAccount.UniqueNo ON tblShopPayment.AccountID = tblShopAccount.AccountID
WHERE tblShopPayment.PaymentCreateDate >=convert(datetime,'9.1.2015',104) and tblShopPayment.PaymentCreateDate <=convert(datetime,'10.1.2015',104) and SysTypeID = 3 order by LastName

　　

2. solving the problem

There are 2 solutions to solve the problem.

One way is rebuild the sql ,  One way is to create index.

I don't want to rebuild the sql. It's so complex and hard to rebuild.

So , I chose to create index.

After creating following indexes, the query reduce to 1 second. Yes, 1s.

--creating following index to improve performance

--creating following index to improve performance

--CREATE NONCLUSTERED INDEX [IXZY_tblShopPaymentDetail1]
--ON [dbo].[tblShopPaymentDetail] ([PaymentID])
--INCLUDE ([ProductID],[ProductName],[Quantity],[Price])

--CREATE NONCLUSTERED INDEX [IXZY_1Students1]
--ON [dbo].[Students] ([Enter_schooltime],[Leave_schooltime])
--INCLUDE ([First_name],[Last_name],[UniqueNo])

--CREATE NONCLUSTERED INDEX [IXZY_1Students12]
--ON [dbo].[Students] ([UniqueNo],[Enter_schooltime],[Leave_schooltime])
--INCLUDE ([First_name],[Last_name])

--CREATE NONCLUSTERED INDEX [IXZY_STAFF1]
--ON [dbo].[Staff] ([AttendStart],[AttendEnd])
--INCLUDE ([FirstName],[LastName],[UniqueNO])

--CREATE NONCLUSTERED INDEX [IXZY_Staff2]
--ON [dbo].[Staff] ([UniqueNO],[AttendStart],[AttendEnd])
--INCLUDE ([FirstName],[LastName])

--CREATE NONCLUSTERED INDEX [IXZY_Parent1]
--ON [dbo].[Parent] ([UniqueNo])
--INCLUDE ([FirstName],[LastName],[Family_ID])