问题
I am using SQL Server 2014 and I have the following T-SQL query:
USE MyDatabase
GO
SELECT
a.ReservationStayID
,c.PMSConfirmationNumber
,c.[PropertyCode]
,a.StayDate
,c.[MTH]
,1 AS 'RN'
,a.PackagePlanCode
,c.[Market Segment Code]
,c.[Status]
,c.[CurrencyCode]
,a.RateAmount
,SUM(a.RateAmount) OVER (PARTITION BY a.ReservationStayID) AS 'CUM_Rate'
,d.[Exchange Rate]
,((a.RateAmount * d.[Exchange Rate]) / 1.15) AS 'Package Revenue Excl VAT'
,c.[Tour Operator]
,c.[Group Booking ID]
,c.[Source of Business]
,c.[Booking Origin (1)]
,c.[Market FINAL]
,ISNULL(ay.[KeyAccountName], 'NA') AS 'Key A/c'
,c.[CreatedOn_RSD]
FROM
ReservationStayDate a
INNER JOIN
[RESERVATIONLIST(2)] c ON c.[ReservationStayID] = a.ReservationStayID
AND c.[MTH] = datename(m, StayDate) + ' ' + cast(datepart(yyyy, StayDate) AS VARCHAR)
INNER JOIN
[PKGREVENUE] d ON d.[ReservationStayID] = a.ReservationStayID
AND d.[StayDate] = a.StayDate
ORDER BY
a.ReservationStayID;
The query runs fine but the output is inconsistent! At times, I get 698,017 rows, and then if I run the query again immediately, I may get 698,020. Another attempt showed 698,025.
This is driving me crazy as my database has not been updated. The SAME query is being run at, say, 1 minute interval and each run is providing an inconsistent output in terms of the number of records! What could be causing this behavior?
I don't know if this additional information will be of any help:
When I the ran the query "as is" above, it gave me 4 records for ReservationStayID = 147469.
I then added the following line to the above query as a filter:
WHERE a.ReservationStayID = 147469
and surprisingly, I got only 2 rows!
[ReservationList(2)] and [PKGREVENUE] are views.
Here are the 2 Views which are invloved:
View 1:
CREATE VIEW [RESERVATIONLIST(2)] AS
SELECT
x.[ReservationStayID],
b.PropertyCode,
c.CreatedOn,
c.CreatedBy,
c.UpdatedBy,
c.UpdatedOn,
xy.Rooms AS [Room Inventory], --added
(xy.Rooms*[DaysInMonth]) AS [RNAvailable], --added
(x.[Nights Spent]/(xy.Rooms*[DaysInMonth])) AS [Occupancy],
c.PMSConfirmationNumber,
a.ArrivalDate AS [Arrival Date],
a.DepartureDate AS [Departure Date],
(a.ArrivalDate - CONVERT(Varchar(10),(CAST(x.CreatedOn as DATE)),(101))) AS 'Booking Lead Time',
a.FirstName + ' ' + a.LastName AS 'Name',
j.ProfileID,
j.EmailAddress AS 'Email',
b.MarketSegmentCode AS 'Market Segment Code',
a.DateOfBirth AS 'Date of Birth',
b.ReservationStatus AS 'Status',
j.Nationality AS 'Nationality',
k.[Country of Residence],
ISNULL(g3.CountryGroup2, 'Not Specified') AS 'Country of Residence 2',
c.ReasonForStayCode AS 'Reason For Stay',
b.RateplanCode,
x.[Rate Plan RSD] AS 'Rate Plan Code',
x.[Room Type RSD] AS 'Room Type',
i.RoomType3 AS 'Room Type 3', -- this code converts the Room Type as per Room Type codes used in the Budget
al.NonRoombundleID,
k3.MpDescription AS 'Meal Plan Description',
ISNULL(k3.MpCode,'RO') AS 'Meal Plan Code',
x.[Adult RSD] AS 'Adult',
x.[Child RSD] AS 'Child',
b.GuestCount AS 'Total Guest',
x.[Nights Spent] AS 'Room Nights',
x.[MTH],
x.[DaysInMonth], --added
x.[Rate] AS 'Room Rate WITH VAT',
c.CurrencyCode,
y.[Pkg Rev (with VAT)],
y.[Pkg Rev (excl VAT)],
x.CreatedOn AS [CreatedOn_RSD],
CONVERT(Varchar(10),(CAST(x.CreatedOn as DATE)),(101)) as [DATE CREATED ON],
datename(m,x.CreatedOn) + ' ' + cast(datepart(yyyy,x.CreatedOn) as varchar) as [Created On (MTH)],
x.[DateOfArrival],
x.[DateOfDeparture],
e.TravelAgencyTypeCode AS 'Source of Business',
c.TAProfileID,
c.PropGroupBookingID AS 'Group Booking ID',
e.Name AS 'Tour Operator',
g.CountryGroup AS 'Market',
c.TAProfileID2,
e2.Name AS 'Booking Origin (1)',
g2.CountryGroup AS 'Booking Origin (2)',
(CASE
WHEN e.TravelAgencyTypeCode = 'DMC'
THEN g2.CountryGroup
ELSE g.CountryGroup
END) AS 'Market (DMC Classified)',
(CASE
WHEN e.TravelAgencyTypeCode = 'DMC' THEN g2.CountryGroup
WHEN c.TAProfileID = '316' AND c.CurrencyCode = 'MUR' THEN 'DB Local'
WHEN c.TAProfileID = '316' THEN 'DB International'
ELSE g.CountryGroup
END) AS 'Market FINAL'
FROM GuestNameInfo a
JOIN GuestStaySummary b ON a.ReservationStayID = b.ReservationStayID
LEFT JOIN ReservationStay c ON c.ReservationStayID = b.ReservationStayID
LEFT JOIN TravelAgency e ON e.TravelAgencyID = c.TAProfileID
LEFT JOIN Market g ON e.CountryCode = g.CountryCode
LEFT JOIN TravelAgency e2 ON e2.TravelAgencyID = c.TAProfileID2
LEFT JOIN Market g2 ON e2.CountryCode = g2.CountryCode
LEFT JOIN CtyRes h ON h.ReservationStayID = a.ReservationStayID
LEFT JOIN Market g3 ON g3.CountryCode = h.CountryCode
LEFT JOIN Profile j ON j.ProfileID = c.ProfileID
LEFT JOIN HotelInventory xy ON xy.PropertyCode = b.PropertyCode
LEFT JOIN
(
SELECT
min(CountryCode) AS [Country of Residence]
, min(ProfileID) AS [Profile ID]
,min(PostalAddressID) AS [Postal Address ID]
FROM PostalAddress
GROUP BY CountryCode,ProfileID,PostalAddressID
) k ON k.[Postal Address ID] = c.PostalAddressID
LEFT JOIN
(
SELECT
ReservationStayID,
datename(m,StayDate) + ' ' + cast(datepart(yyyy,StayDate) as varchar) as [MTH],
datediff(day, dateadd(day, 1-day(StayDate), StayDate),
dateadd(month, 1, dateadd(day, 1-day(StayDate), StayDate))) AS [DaysInMonth],
min(adultcount) as 'Adult RSD',
min(childcount) as 'Child RSD',
min(RoomTypeCode) AS 'Room Type RSD',
min(PackagePlanCode) AS 'Rate Plan RSD',
count(*) AS [Nights Spent],
avg(RateAmount) as [Rate],
min(CreatedOn) as CreatedOn,
min(StayDate) as [DateOfArrival],
max(StayDate) as [DateOfDeparture]
FROM ReservationStayDate
GROUP BY ReservationStayID, datename(m,StayDate) + ' ' + cast(datepart(yyyy,StayDate) as varchar), datediff(day, dateadd(day, 1-day(StayDate), StayDate),
dateadd(month, 1, dateadd(day, 1-day(StayDate), StayDate)))
) x ON x.ReservationStayID = b.ReservationStayID
LEFT JOIN RoomCat i ON b.PropertyCode = i.Property AND [Room Type RSD] = i.RoomType
LEFT JOIN
(SELECT datename(m,StayDate) + ' ' + cast(datepart(yyyy,StayDate) as varchar) AS [MTH_PKGREV],
[ReservationStayId], SUM([Package Revenue with VAT]) AS 'Pkg Rev (with VAT)',
SUM([Package Revenue excl VAT]) AS 'Pkg Rev (excl VAT)'
FROM PKGREVENUE
GROUP BY datename(m,StayDate) + ' ' + cast(datepart(yyyy,StayDate) as varchar),[ReservationStayId]
) y ON y.[ReservationStayId] = b.ReservationStayID AND [MTH] = datename(m,[MTH_PKGREV]) + ' ' + cast(datepart(yyyy,[MTH_PKGREV]) as varchar)
LEFT JOIN
(
SELECT ReservationStayID, MTH, NonRoombundleID
FROM NONROOMBUNDLEID
group by ReservationStayID, MTH, NonRoombundleID
)al ON al.ReservationStayID = x.ReservationStayID AND al.[MTH] = x.[MTH]
LEFT JOIN NonRoomBundle k2 ON K2.NonRoomBundleID = al.NonRoombundleID
LEFT JOIN MealPlan k3 ON k3.MpDescription = k2.Description
WHERE a.PrimaryGuest = '+'
View 2:
CREATE VIEW [PKGREVENUE] AS
SELECT
ReservationStayDate.ReservationStayID AS [ReservationStayId]
,ReservationStay.PMSConfirmationNumber AS [PmsConfirmationNumber]
,ReservationStayDate.StayDate AS [StayDate]
,ReservationStayDate.RateAmount AS [RateAmount]
,ReservationStay.CurrencyCode AS [CurrencyCode]
,CAST(ROUND(ISNULL((1/CA.SellRate),1),2) as numeric (36,2)) AS 'Exchange Rate' -- since MUR is not in the Exchange Rate Table, this replaces all NULL values for MUR by 1.00
,CAST(ROUND(ReservationStayDate.RateAmount * ISNULL((1/CA.SellRate),1),0) as numeric (36,0)) AS 'Package Revenue with VAT'
,(CAST(ROUND(ReservationStayDate.RateAmount * ISNULL((1/CA.SellRate),1),0)/1.15 as numeric (36,0))) AS 'Package Revenue excl VAT'
FROM
ReservationStayDate
INNER JOIN ReservationStay ON ReservationStay.ReservationStayID = ReservationStayDate.ReservationStayID
OUTER APPLY
(
SELECT TOP(1) ExchangeRate.SellRate
FROM ExchangeRate
WHERE
ExchangeRate.ToCurrencyCode = ReservationStay.CurrencyCode
AND ExchangeRate.EffectiveDate <= ReservationStayDate.StayDate
ORDER BY ExchangeRate.EffectiveDate DESC
) AS CA
回答1:
Thanks everyone who provided help to my problem. I even got a negative and I don't know why! Anyway, I would like to provide an update here as to how I solved the problem. I had a deep look into the deterministic and non-deterministic functions as suggested by some of you. However, I could not locate any such functions in my query and views that were causing the main query to misbehave and give inconsistent results.
I gave the GROUP BY clause a try in my main query (although I did not need that clause). And behold, the problem was solved!! Now, my query is giving me the same number of records at each attempt. As to why did the GROUP BY clause solve the problem, I have absolutely no idea. Just wanted to share this with the community here. May be someone can shed some light on the magical powers of the GROUP BY clause! :-)
回答2:
Not all functions in Sql Server are deterministic. Check out Deterministic and Nondeterministic Functions
I don't see anything that is non-deterministic in your query but you might want to look at the views that you join on to and make sure that there is nothing there that is in the non deterministic list.
回答3:
This always happens when there is a mixed-up or not consistent use of aliases in statements that contain:
1-order by
2-group by
3-where clauses
Like in this line:
GROUP BY datename(m,StayDate) + ' ' + cast(datepart(yyyy,StayDate)
maybe the field StayDate exists in different parts of the query. Sometimes the optimizer takes a different path and chooses the other field. Aliases direct the optimizer always to take the proper field.
来源：https://stackoverflow.com/questions/33736997/why-is-my-t-sql-query-returning-inconsistent-output