nhibernate is removing join in sub query - nhibernate

I'm working on a conversion project .net 2.0 to .net 4.5.1 and have run into an issue with NHibernate HQL. My problem is with a sub query that is added at run time which is stored in the database for filtering purposes and appended to the HQL before the query is tanslated by NH. The two left joins in the sub query are removed.
the query before translation:
Select allergy From Allergy allergy left join allergy.HealthcareWorker healthcareWorker where (1=1) and healthcareWorker.Id = :healthcareWorkerId and ((
allergy.Id in ( Select allergy.id From Allergy allergy
left join allergy.HealthcareWorker healthcareWorker
left join healthcareWorker.LatticeFacility latticeFacility
Where latticeFacility.Id in (134,342))))
after transformation:
select allergy0_.AllergyID as AllergyID41_, allergy0_.RowVersionNumber as RowVersi2_41_, allergy0_.AllergyDate as AllergyD3_41_, allergy0_.Comments as Comments41_, allergy0_.InactivationDate as Inactiva5_41_, allergy0_.CreatedAt as CreatedAt41_, allergy0_.CreatedBy as CreatedBy41_, allergy0_.LastModAt as LastModAt41_, allergy0_.LastModBy as LastModBy41_, allergy0_.HealthcareWorkerID as Healthc10_41_, allergy0_.AllergyTypeID as Allergy11_41_, allergy0_.AllergySubstanceID as Allergy12_41_, allergy0_.MedicationItemID as Medicat13_41_, allergy0_.MedicalPractitionerConfirmedID as Medical14_41_, allergy0_.InactivationReasonID as Inactiv15_41_, case when allergy0_.InactivationDate is not null then case when allergy0_.InactivationReasonID is not null then 0 else 1 end else 1 end as formula4_ from tblAllergy allergy0_ left outer join tblHealthcareWorker healthcare1_ on allergy0_.HealthcareWorkerID=healthcare1_.HealthcareWorkerID where 1=1 and healthcare1_.HealthcareWorkerID=#p0 and (allergy0_.AllergyID in (select allergy2_.AllergyID from tblAllergy allergy2_ where latticefac4_.LatticeFacilityID in (134,342))
This generates an exception The multi-part identifier "latticefac4_.LatticeFacilityID" could not be bound. Obviously because the joins have been removed from the sub query.
I'm am new to NHibernate so any suggestions are appreciated.
Thanks

So this ended up being an issue with NHibernate not recognising the table aliases. Turns out the sub query aliases for the joins need to be unique from the external query aliases.

Related

MS Access SQL sub Query using outer query result

I'm attempting to run a sub query based on the result of an outer query. The issue that I am having is that instead of using the outer query, I get a prompt for a value from the subquery.
SELECT Facilities.CustomerName, Facilities.FacilityName,
Facilities.AnnualPlan, Facilities.AppCo1,
(SELECT YeildDB.CornYield
FROM YeildDB
WHERE Facilites.AppCo1 = YeildDB.FIPS) AS Expr1
FROM Facilities
The goal is that the sub query should use the value from Facilities.AppCo1 to match with the value in YeildDB.FIPS and then return the corresponding value in YeildDB.CornYeild.
Currently I get a prompt asking for the YeildDB.FIPS value instead of the sub query using the outer query value.
Your code should work. But you can also express this using a LEFT JOIN:
SELECT Facilities.CustomerName, Facilities.FacilityName,
Facilities.AnnualPlan, Facilities.AppCo1,
YeildDB.CornYield
FROM Facilities LEFT JOIN
YeildDB
ON Facilties.AppCo1 = YeildDB.FIPS;
I noticed that you misspelled Facilities -- and that is probably why your version doesn't work. This is one reason to use table aliases:
SELECT f.CustomerName, f.FacilityName,
f.AnnualPlan, f.AppCo1,
y.CornYield
FROM Facilities as f LEFT JOIN
YeildDB as y
ON f.AppCo1 = y.FIPS;
Your sub query may be returning multiple values, hence the prompt asking you to specify which one you want. You can fix this (or at least hide this issue) by specifying top 1:
SELECT Facilities.CustomerName, Facilities.FacilityName,
Facilities.AnnualPlan, Facilities.AppCo1,
(SELECT TOP 1 YeildDB.CornYield
FROM YeildDB
WHERE Facilites.AppCo1 = YeildDB.FIPS) AS Expr1
FROM Facilities

MS Access INNER JOIN/LEFT JOIN problems

I have the following SQL string which tries to combine an INNER JOIN with a LEFT JOIN in the FROM section.
As you can see I use table VIP_APP_VIP_SCENARIO_DETAIL_LE to perform the query. When I use it against this table, Access give me an "Invalid Operation" error.
Interestingly, when I use the EXACT same query using the VIP_APP_VIP_SCENARIO_DETAIL_BUDGET or VIP_APP_VIP_SCENARIO_DETAIL_ACTUALS table, it performs flawlessly.
So why would it work on two tables but not the other? All fields are in all tables and the data types are correct.
As a side note: on the query with the error, if I change the LEFT JOIN to an INNER JOIN, it runs with no problem! I really need a LEFT JOIN though.
SELECT
D.MATERIAL_NUMBER,
D.MATERIAL_DESCRIPTION,
D.PRODUCTION_LOT_SIZE,
D.STANDARDS_NAME,
D.WORK_CENTER,
S.OP_SHORT_TEXT,
S.OPERATION_CODE,
D.LINE_SPEED_UPM,
D.PERCENT_STD,
D.EQUIPMENT_SU,
D.EQUIPMENT_CU,
D.OPERATOR_NUM,
V.COSTING_LOT_SIZE,
V.VOL_TOTAL_ADJ
FROM
([STDS_SCENARIO: TEST] AS D INNER JOIN MASTER_SUMMARY AS S ON
D.MATERIAL_NUMBER = S.MATERIAL_NUMBER AND D.WORK_CENTER = S.WORK_CENTER)
LEFT JOIN
(SELECT ITEM_CODE, COSTING_LOT_SIZE, VOL_TOTAL_ADJ
FROM
VIP_APP_VIP_SCENARIO_DETAIL_LE
WHERE SCENARIO_ID = 16968) AS V ON D.MATERIAL_NUMBER = V.ITEM_CODE
ORDER BY D.MATERIAL_NUMBER, D.STANDARDS_NAME, S.OPERATION_CODE;
tried to mock this up in SQL server with some tables of my own, but the structure seemed to work, this follows the pattern referenced above. (hopefully no syntax errors left here)
SELECT * FROM (
select
D.MATERIAL_NUMBER,
D.MATERIAL_DESCRIPTION,
D.PRODUCTION_LOT_SIZE,
D.STANDARDS_NAME,
D.WORK_CENTER,
S.OP_SHORT_TEXT,
S.OPERATION_CODE,
D.LINE_SPEED_UPM,
D.PERCENT_STD,
D.EQUIPMENT_SU,
D.EQUIPMENT_CU,
D.OPERATOR_NUM
FROM [STDS_SCENARIO: TEST] D
INNER JOIN MASTER_SUMMARY S
ON D.MATERIAL_NUMBER = S.MATERIAL_NUMBER AND D.WORK_CENTER = S.WORK_CENTER) AS J
LEFT JOIN
(SELECT ITEM_CODE, COSTING_LOT_SIZE, VOL_TOTAL_ADJ
FROM
VIP_APP_VIP_SCENARIO_DETAIL_LE
WHERE SCENARIO_ID = 16968) AS V ON J.MATERIAL_NUMBER = V.ITEM_CODE
ORDER BY J.MATERIAL_NUMBER, J.STANDARDS_NAME, J.OPERATION_CODE;
Had help from a friend and we discovered that it was a casting problem between a linked Oracle table and the Access table. To fix the problem we casted both sides of the linked fields to a string:
CSTR(D.[MATERIAL_NUMBER]) = CSTR(V.[ITEM_CODE])

SQL Server : multi-join with tuple IN clause

I'm trying to join 4 tables that have a somewhat complex relationship. Because of where this will be used, it needs to be contained in a single query, but I'm having trouble since the primary query and the IN clause query both join 2 tables together and the lookup is on two columns.
The goal is to input a SalesNum and SalesType and have it return the Price
Tables and relationships:
sdShipping
SalesNum[1]
SalesType[2]
Weight[3]
sdSales
SalesNum[1]
SalesType[2]
Zip[4]
spZones
Zip[4]
Zone[5]
spPrices
Zone[5]
Price
Weight[3]
Here's my latest attempt in T-SQL:
SELECT
spp.Price
FROM
spZones AS spz
LEFT OUTER JOIN
spPrices AS spp ON spz.Zone = spp.Zone
WHERE
(spp.Weight, spz.Zip) IN (SELECT ship.Weight, sales.Zip
FROM sdShipping AS ship
LEFT OUTER JOIN sdSales AS sales ON sales.SalesNum = ship.SalesNum
AND sales.SalesType = ship.SalesType
WHERE sales.SalesNum = (?)
AND ship.SalesType = (?));
SQL Server Management Studio says I have an error in my syntax near ',' (appropriately useless error message). Does anybody have any idea whether this is even allowed in Microsoft's version of SQL? Is there perhaps another way to accomplish it? I've seen the multi-key IN questions answered on here, but never in the case where both sides require a JOIN.
Many databases do support IN on tuples. SQL Server is not one of them.
Use EXISTS instead:
SELECT spp.Price
FROM spZones spz LEFT OUTER JOIN
spPrices spp
ON spz.Zone = spp.Zone
WHERE EXISTS (SELECT 1
FROM sdShipping ship LEFT JOIN
sdSales sales
ON sales.SalesNum = ship.SalesNum AND
sales.SalesType = ship.SalesType
WHERE spp.Weight = ship.Weight AND spz.Zip = sales.Zip AND
sales.SalesNum = (?) AND
ship.SalesType = (?)
);

Timeout running SQL query

I'm trying to using the aggregation features of the django ORM to run a query on a MSSQL 2008R2 database, but I keep getting a timeout error. The query (generated by django) which fails is below. I've tried running it directs the SQL management studio and it works, but takes 3.5 min
It does look it's aggregating over a bunch of fields which it doesn't need to, but I wouldn't have though that should really cause it to take that long. The database isn't that big either, auth_user has 9 records, ticket_ticket has 1210, and ticket_watchers has 1876. Is there something I'm missing?
SELECT
[auth_user].[id],
[auth_user].[password],
[auth_user].[last_login],
[auth_user].[is_superuser],
[auth_user].[username],
[auth_user].[first_name],
[auth_user].[last_name],
[auth_user].[email],
[auth_user].[is_staff],
[auth_user].[is_active],
[auth_user].[date_joined],
COUNT([tickets_ticket].[id]) AS [tickets_captured__count],
COUNT(T3.[id]) AS [assigned_tickets__count],
COUNT([tickets_ticket_watchers].[ticket_id]) AS [tickets_watched__count]
FROM
[auth_user]
LEFT OUTER JOIN [tickets_ticket] ON ([auth_user].[id] = [tickets_ticket].[capturer_id])
LEFT OUTER JOIN [tickets_ticket] T3 ON ([auth_user].[id] = T3.[responsible_id])
LEFT OUTER JOIN [tickets_ticket_watchers] ON ([auth_user].[id] = [tickets_ticket_watchers].[user_id])
GROUP BY
[auth_user].[id],
[auth_user].[password],
[auth_user].[last_login],
[auth_user].[is_superuser],
[auth_user].[username],
[auth_user].[first_name],
[auth_user].[last_name],
[auth_user].[email],
[auth_user].[is_staff],
[auth_user].[is_active],
[auth_user].[date_joined]
HAVING
(COUNT([tickets_ticket].[id]) > 0 OR COUNT(T3.[id]) > 0 )
EDIT:
Here are the relevant indexes (excluding those not used in the query):
auth_user.id (PK)
auth_user.username (Unique)
tickets_ticket.id (PK)
tickets_ticket.capturer_id
tickets_ticket.responsible_id
tickets_ticket_watchers.id (PK)
tickets_ticket_watchers.user_id
tickets_ticket_watchers.ticket_id
EDIT 2:
After a bit of experimentation, I've found that the following query is the smallest that results in the slow execution:
SELECT
COUNT([tickets_ticket].[id]) AS [tickets_captured__count],
COUNT(T3.[id]) AS [assigned_tickets__count],
COUNT([tickets_ticket_watchers].[ticket_id]) AS [tickets_watched__count]
FROM
[auth_user]
LEFT OUTER JOIN [tickets_ticket] ON ([auth_user].[id] = [tickets_ticket].[capturer_id])
LEFT OUTER JOIN [tickets_ticket] T3 ON ([auth_user].[id] = T3.[responsible_id])
LEFT OUTER JOIN [tickets_ticket_watchers] ON ([auth_user].[id] = [tickets_ticket_watchers].[user_id])
GROUP BY
[auth_user].[id]
The weird thing is that if I comment out any two lines in the above, it runs in less that 1s, but it doesn't seem to matter which lines I remove (although obviously I can't remove a join without also removing the relevant SELECT line).
EDIT 3:
The python code which generated this is:
User.objects.annotate(
Count('tickets_captured'),
Count('assigned_tickets'),
Count('tickets_watched')
)
A look at the execution plan shows that SQL Server is first doing a cross-join on all the table, resulting in about 280 million rows, and 6Gb of data. I assume that this is where the problem lies, but why is it happening?
SQL Server is doing exactly what it was asked to do. Unfortunately, Django is not generating the right query for what you want. It looks like you need to count distinct, instead of just count: Django annotate() multiple times causes wrong answers
As for why the query works that way: The query says to join the four tables together. So say an author has 2 captured tickets, 3 assigned tickets, and 4 watched tickets, the join will return 2*3*4 tickets, one for each combination of tickets. The distinct part will remove all the duplicates.
what about this?
SELECT auth_user.*,
C1.tickets_captured__count
C2.assigned_tickets__count
C3.tickets_watched__count
FROM
auth_user
LEFT JOIN
( SELECT capturer_id, COUNT(*) AS tickets_captured__count
FROM tickets_ticket GROUP BY capturer_id ) AS C1 ON auth_user.id = C1.capturer_id
LEFT JOIN
( SELECT responsible_id, COUNT(*) AS assigned_tickets__count
FROM tickets_ticket GROUP BY responsible_id ) AS C2 ON auth_user.id = C2.responsible_id
LEFT JOIN
( SELECT user_id, COUNT(*) AS tickets_watched__count
FROM tickets_ticket_watchers GROUP BY user_id ) AS C3 ON auth_user.id = C3.user_id
WHERE C1.tickets_captured__count > 0 OR C2.assigned_tickets__count > 0
--WHERE C1.tickets_captured__count is not null OR C2.assigned_tickets__count is not null -- also works (I think with beter performance)

Whats wrong with this nested query?

I am trying to write a query to return the id of the latest version of a market index stored in a database.
SELECT miv.market_index_id market_index_id from ref_market_index_version miv
INNER JOIN ref_market_index mi ON miv.market_index_id = mi.id
WHERE mi.short_name='dow30'
AND miv.version_num = (SELECT MAX(m1.version_num) FROM ref_market_index_version m1 INNER JOIN ref_market_index m2 ON m1.market_index_id = m2.id )
The above SQL statement can be (roughly) translated into the form:
SELECT some columns FROM SOME CRITERIA MATCHED TABLES
WHERE mi.short_name='some name'
AND miv.version_num = SOME NUMBER
What I don't understand is that when I supply an actual number (instead of a sub query), the SQL statement works - also, when I test the SUB query used to determine the latest version number, that also works - however, when I attempt to use the result returned by sub query in the outer (parent?) query, it returns 0 rows - what am I doing wrong here?
Incidentally, I also tried an IN CLAUSE instead of the strict equality match i.e.
... AND miv.version_num IN (SUB QUERY)
That also resulted in 0 rows, although as before, when running the parent query with a hard coded version number, I get 1 row returned (as expected).
BTW I am using postgeresql, but I prefer the solution to be db agnostic.
The problem is probably that the max(version_num) doesn't exist for 'dow30'.
Try the following correlated subquery:
SELECT miv.market_index_id market_index_id
from ref_market_index_version miv INNER JOIN
ref_market_index mi
ON miv.market_index_id = mi.id
WHERE mi.short_name='dow30' AND
miv.version_num = (SELECT MAX(m1.version_num)
FROM ref_market_index_version m1 INNER JOIN
ref_market_index m2
ON m1.market_index_id = m2.id
where m1.short_name = 'dow30'
)
I added the where clause in the subquery.