How do i select a Distinct value from a select statement with LEFT JOINS?
The value I'm after is one of either s_id from trainingTbl or setName from setsTbl.
The full string is provided below.
Dim strQuery As String =
"SELECT *
FROM userAssessmentTbl
LEFT JOIN trainingTbl ON userAssessmentTbl.tt_id = trainingTbl.tt_id
LEFT JOIN setsTbl ON trainingTbl.s_id = setsTbl.s_id
LEFT JOIN outcomesTbl ON userAssessmentTbl.o_id = outcomesTbl.o_id
WHERE UserId = #UserId
ORDER BY t_date DESC "
Try with GROUP BY for uniqueness
SELECT *
FROM userAssessmentTbl
LEFT JOIN trainingTbl ON userAssessmentTbl.tt_id = trainingTbl.tt_id LEFT JOIN setsTbl ON trainingTbl.s_id = setsTbl.s_id
LEFT JOIN outcomesTbl ON userAssessmentTbl.o_id = outcomesTbl.o_id
WHERE UserId = #UserId
GROUP BY trainingTbl.s_id
ORDER BY t_date DESC
try this
SELECT DISTINCT trainingTbl.s_id FROM
userAssessmentTbl LEFT JOIN trainingTbl ON userAssessmentTbl.tt_id = trainingTbl.tt_id
LEFT JOIN setsTbl ON trainingTbl.s_id = setsTbl.s_id
LEFT JOIN outcomesTbl ON userAssessmentTbl.o_id = outcomesTbl.o_id
WHERE UserId = #UserId ORDER BY t_date DESC
or this (not sure what exactly you need)
SELECT DISTINCT trainingTbl.s_id, setsTbl.setName FROM
userAssessmentTbl LEFT JOIN trainingTbl ON userAssessmentTbl.tt_id = trainingTbl.tt_id
LEFT JOIN setsTbl ON trainingTbl.s_id = setsTbl.s_id
LEFT JOIN outcomesTbl ON userAssessmentTbl.o_id = outcomesTbl.o_id
WHERE UserId = #UserId ORDER BY t_date DESC
In the first place your problem is that you are using select * (A SQL antipattern and something that should NEVER appear in production code) and thus each record is unique so adding distinct or group by will not work.
It is not the left joins causing the proble, an inner join would have the same problem. The problem is that you have a one-to-many relationship between the tables and thus have multiple records when you join them. If you only want one record per id in the first table, then you must specify which record or individual data field in the other tables you want - either use aggregate functions to get the record you want to match or do some sort of filtering in the join to make sure you have a one-to-one relationship. Without knowing your data and your business rules, I cannot suggest what is best to do.
Related
This SQL query needs to be done in ACCESS.
I am trying to do a subquery on the total sales, but I want to link the sale to the province AND to product. The below query will work with one or the other: (po.product_name = allp.all_products) AND (p.province = allp.all_province); -- but it will no take both.
I will be including every month into this query, once I can figure out the subquery on with two criteria.
Select
p.province as [Province],
po.product_name as [Product],
all_price
FROM
(purchase_order po
INNER JOIN person p
on p.person_id = po.person_id)
left join
(
select
po1.product_name AS [all_products],
sum(pp1.price) AS [all_price],
p1.province AS [all_province]
from (purchase_order po1
INNER JOIN product pp1
on po1.product_name = pp1.product_name)
INNER JOIN person p1
on po1.person_id = p1.person_id
group by po1.product_name, pp1.price, p1.province
)
as allp
on (po.product_name = allp.all_products) AND (p.province = allp.all_province);
Make the first select sql into a table by giving it an alias and join table 1 to table 2. I don't have your table structure or data to test it but I think this will lead you down the right path:
select table1.*, table2.*
from
(Select
p.province as [Province],
po.product_name as [Product]
--removed this ,all_price
FROM
(purchase_order po
INNER JOIN person p
on p.person_id = po.person_id) table1
left join
(
select
po1.product_name AS [all_products],
sum(pp1.price) AS [all_price],
p1.province AS [all_province]
from (purchase_order po1
INNER JOIN product pp1
on po1.product_name = pp1.product_name)
INNER JOIN person p1
on po1.person_id = p1.person_id
group by po1.product_name, pp1.price, p1.province --check your group by, I dont think you want pp1.price here if you want to aggregate
) as table2 --changed from allp
on (table1.product = table2.all_products) AND (table1.province = table2.all_province);
I have a query of SQL that is a join of multiple tables, it is returning duplicate rows and after hours of going through it can't find out where its going wrong
SELECT
StkItem.iUOMStockingUnitID,
_etblUnits1.cUnitCode as 'parkSize',
_etblUnits2.cUnitCode as 'quantitySize',
InvNum.fInvTotExclForeign,
[_btblInvoiceLines].*,
[_rtblCountry].cCountryName,
[CurrencyHist].fBuyRate,
Vendor.Name,
InvNum.OrderDate,
InvNum.InvNumber
FROM
[dbo].[_btblInvoiceLines]
LEFT JOIN
StkItem ON StkItem.StockLink = [_btblInvoiceLines].iStockCodeID
LEFT JOIN
_etblUnits as _etblUnits1 ON _etblUnits1.idunits = StkItem.iUOMDefSellUnitID
LEFT JOIN
_etblUnits as _etblUnits2 ON _etblUnits2.idunits = StkItem.iUOMStockingUnitID
LEFT JOIN
InvNum ON iInvoiceID = AutoIndex
LEFT JOIN
Vendor ON Vendor.DCLink = InvNum.AccountID
LEFT JOIN
[_rtblCountry] ON [_rtblCountry].idCountry = Vendor.iCountryID
LEFT JOIN
[CurrencyHist] ON InvNum.ForeignCurrencyID = [CurrencyHist].iCurrencyID
WHERE
OrderNum = ''
AND [CurrencyHist].iCurrencyID = (SELECT TOP 1 iCurrencyID
FROM [CurrencyHist]
WHERE iCurrencyID = InvNum.ForeignCurrencyID
ORDER BY idCurrencyHist DESC)
Here is the query, any help will be highly appreciated, thanks in advance
From your previous comments, The problem is coming when you join [CurrencyHist]. From the name, it seems it's a history table and so must be having multiple rows as a history for each currency. To eliminate duplicate rows, you should join with the latest updated record for the particular currency. So, your query could be like below,
SELECT StkItem.iUOMStockingUnitID,
_etblUnits1.cUnitCode as 'parkSize',
_etblUnits2.cUnitCode as 'quantitySize',
InvNum.fInvTotExclForeign,
[_btblInvoiceLines].*,
[_rtblCountry].cCountryName,
[CurrencyHist].fBuyRate,
Vendor.Name,
InvNum.OrderDate,
InvNum.InvNumber
FROM [dbo].[_btblInvoiceLines]
LEFT JOIN StkItem ON StkItem.StockLink = [_btblInvoiceLines].iStockCodeID
LEFT JOIN _etblUnits as _etblUnits1 ON _etblUnits1.idunits = StkItem.iUOMDefSellUnitID
LEFT JOIN _etblUnits as _etblUnits2 ON _etblUnits2.idunits = StkItem.iUOMStockingUnitID
LEFT JOIN InvNum ON iInvoiceID = AutoIndex
LEFT JOIN Vendor ON Vendor.DCLink = InvNum.AccountID
LEFT JOIN [_rtblCountry] ON [_rtblCountry].idCountry = Vendor.iCountryID
LEFT JOIN (SELECT DENSE_RANK() over (partition by [CurrencyHist].iCurrencyID order by [CurrencyHist].LastUpdated desc) as rn,[CurrencyHist].iCurrencyID as 'iCurrencyID'
FROM [CurrencyHist] AS [CurrencyHist]
)[CurrencyHist] ON InvNum.ForeignCurrencyID = [CurrencyHist].iCurrencyID
and [CurrencyHist].rn=1
WHERE OrderNum = '' AND
[CurrencyHist].iCurrencyID = (SELECT TOP 1 iCurrencyID
FROM [CurrencyHist]
WHERE iCurrencyID = InvNum.ForeignCurrencyID
ORDER BY idCurrencyHist DESC)
Note : I have assumed that CurrencyHist table has a LastUpdated with DateTime datatype Column
Hello i am making schema for purchasing orders these orders can be ordered by certain user and then received by another user.
so i created the below schema.
Schema
The issue is when UserID column in PurchaseOrders and Deliveries tables has different values the query returns no records.
Query
SELECT
dbo.Users.FirstName,
dbo.Users.LastName,
dbo.PurchaseOrders.PurchaseOrderDate,
dbo.Deliveries.ExpectedDeliveryDate,
dbo.Deliveries.ActualDeliveryDate
FROM dbo.PurchaseOrders
INNER JOIN dbo.Users
ON dbo.PurchaseOrders.UserID = dbo.Users.UserID
INNER JOIN dbo.Deliveries
ON dbo.PurchaseOrders.PurchaseOrderID = dbo.Deliveries.PurchaseOrderID
AND dbo.Users.UserID = dbo.PurchaseOrders.UserID
AND dbo.Users.UserID = dbo.Deliveries.UserID
You need two different joins to Users. You also need to learn to use table aliases:
SELECT pu.FirstName as purchase_FirstName, pu.LastName as purchase_LastName,
du.FirstName as delivery_FirstName, du.LastName as delivery_LastName,
po.PurchaseOrderDate,
d.ExpectedDeliveryDate, d.ActualDeliveryDate
FROM dbo.PurchaseOrders po JOIN
dbo.Deliveries d
ON po.PurchaseOrderID = d.PurchaseOrderID JOIN
dbo.Users pu
ON p.UserID = pu.UserID JOIN
dbo.Users du
ON d.UserId = du.UserId;
Your query returns no records because of this condition:
AND dbo.Users.UserID = dbo.PurchaseOrders.UserID
AND dbo.Users.UserID = dbo.Deliveries.UserID
This obviously means that dbo.PurchaseOrders.UserID = dbo.Deliveries.UserID. So, if this is not true, then no records match the condition.
When you use Inner Join, if the data doesnt match, you will not get any records. You need to use LEFT JOIN and also the second join doesnt need condition with user id. Try the below query.
SELECT
dbo.Users.FirstName,
dbo.Users.LastName,
dbo.PurchaseOrders.PurchaseOrderDate,
dbo.Deliveries.ExpectedDeliveryDate,
dbo.Deliveries.ActualDeliveryDate
FROM dbo.PurchaseOrders
INNER JOIN dbo.Users
ON dbo.PurchaseOrders.UserID = dbo.Users.UserID
LEFT JOIN dbo.Deliveries
ON dbo.PurchaseOrders.PurchaseOrderID = dbo.Deliveries.PurchaseOrderID
I'm currently working with database, but I've got stuck with a select query.
However, I'm not database expert.
The query should return the data from a table that has two relationships of many to many.
This is my tables Diagram that would shows the concept of my question
The Select Query should View three columns, which are VidTbl.Name, ActorTbl.Name and SubTitelTbl.name.
So, I've read and search in the Internet and I've given tries
First try
SELECT
VidTbl.NAME AS Video_Titel_Name,
ActorTbl.NAME AS Actor_Name
FROM ActorInVid
INNER JOIN VidTbl
ON VidTbl.Id = ActorInVid.FKVidId
INNER JOIN ActorTbl
ON ActorTbl.Id = ActorInVid.FKActorId
UNION all
SELECT
VidTbl.NAME AS Video_Titel_Name,
SubTitelTbl.NAME AS SubTitel_Langu
FROM SubTitelInVid
INNER JOIN VidTbl
ON VidTbl.Id = SubTitelInVid.FKVidId
INNER JOIN SubTitelTbl
ON SubTitelTbl.Id = SubTitelInVid.FKSTId
The Result I've got, it was wrong
Then I tried another way to solve this problem, but again I've got another error
second try
SELECT Temp1.*
From (SELECT VidTbl.Id AS Video_Id,
VidTbl.NAME AS Video_Titel_Name,
ActorTbl.NAME AS Actor_Name
FROM ActorInVid
INNER JOIN VidTbl
ON VidTbl.Id = ActorInVid.FKVidId
INNER JOIN ActorTbl
ON ActorTbl.Id = ActorInVid.FKActorId) AS Temp1
SELECT Temp2.*
FROM (SELECT VidTbl.Id AS Video_Id,
SubTitelTbl.NAME AS SubTitel_Langu
FROM SubTitelInVid
INNER JOIN VidTbl
ON VidTbl.Id = SubTitelInVid.FKVidId
INNER JOIN SubTitelTbl
ON SubTitelTbl.Id = SubTitelInVid.FKSTId) AS Temp2
SELECT *
FROM VidTbl
INNER JOIN Temp1
on Temp1.Video_Id = VidTbl.Id
INNER JOIN Temp2
on Temp2.Video_Id = VidTbl.Id
The error, I've got in the last select that was wrong
Thanks a lot for your help any ways
I wish that my question is clear and useful
Thanks again.
You are close. This should work...
SELECT
VidTbl.Name,
ActorTbl.Name,
SubTitelTbl.name
FROM VidTbl
INNER JOIN ActorInVid ON VidTbl.Id = ActorInVid.FKVidId
INNER JOIN ActorTbl ON ActorTbl.Id = ActorInVid.FKActorId
INNER JOIN SubTitelInVid ON VidTbl.Id = SubTitelInVid.FKVidId
INNER JOIN SubTitelTbl ON SubTitelTbl.Id = SubTitelInVid.FKSTId
SELECT DISTINCT vt.Name, at.Name, st.Name
FROM VidTbl vt
JOIN ActionInVid aiv ON aiv.VidId = vt.Id
JOIN SubtitleInVid siv ON siv.VidId = vt.Id
JOIN ActorTbl at ON at.Id = aiv.ActorId
JOIN SubTitleTbl st ON st.Id = siv.STId
I have the following requisites for a query:
Needs to ordered on a inner joined table (see from_products_products below),
Allow duplicates names on from_products_products
It cannot return duplicates records on the origin table (distinct on products.id).
The following query will eliminate the duplicate names, which is not desired, as I had to put a distinct on from_products_products.name because of the use in order by:
SELECT DISTINCT ON (from_products_products.name, products.id) "products".* FROM "products"
INNER JOIN "suppliers_plugin_source_products" ON "suppliers_plugin_source_products"."to_product_id" = "products"."id"
INNER JOIN "products" "from_products_products" ON "from_products_products"."id" = "suppliers_plugin_source_products"."from_product_id"
INNER JOIN "suppliers_plugin_source_products" "sources_from_products_products_join" ON "sources_from_products_products_join"."to_product_id" = "products"."id"
INNER JOIN "suppliers_plugin_suppliers" ON "suppliers_plugin_suppliers"."id" = "sources_from_products_products_join"."supplier_id"
WHERE "products"."profile_id" = 45781 AND (("products"."type" IN ('SuppliersPlugin::DistributedProduct') OR "products"."type" IS NULL)) AND (products.archived <> true)
ORDER BY from_products_products.name ASC, products.id
Using GROUP BY has the same effect and also don't remove duplicates;
The original query that gives duplicate products when the INNER JOIN doesn't match any product:
SELECT "products".* FROM "products"
INNER JOIN "suppliers_plugin_source_products" ON "suppliers_plugin_source_products"."to_product_id" = "products"."id"
INNER JOIN "products" "from_products_products" ON "from_products_products"."id" = "suppliers_plugin_source_products"."from_product_id"
INNER JOIN "suppliers_plugin_source_products" "sources_from_products_products_join" ON "sources_from_products_products_join"."to_product_id" = "products"."id"
INNER JOIN "suppliers_plugin_suppliers" ON "suppliers_plugin_suppliers"."id" = "sources_from_products_products_join"."supplier_id"
WHERE "products"."profile_id" = 45781 AND (("products"."type" IN ('SuppliersPlugin::DistributedProduct') OR "products"."type" IS NULL)) AND (products.archived <> true)
ORDER BY from_products_products.name ASC
So, how to overcome this on PostgreSQL?
PS: This is part of open-source software Noosfero-ecosol
Does this do what you want?
with t as (
SELECT DISTINCT ON (products.id) "products".*,
from_products_products.name as from_products_name
FROM "products"
INNER JOIN "suppliers_plugin_source_products" ON "suppliers_plugin_source_products"."to_product_id" = "products"."id"
INNER JOIN "products" "from_products_products" ON "from_products_products"."id" = "suppliers_plugin_source_products"."from_product_id"
INNER JOIN "suppliers_plugin_source_products" "sources_from_products_products_join" ON "sources_from_products_products_join"."to_product_id" = "products"."id"
INNER JOIN "suppliers_plugin_suppliers" ON "suppliers_plugin_suppliers"."id" = "sources_from_products_products_join"."supplier_id"
WHERE "products"."profile_id" = 45781 AND (("products"."type" IN ('SuppliersPlugin::DistributedProduct') OR "products"."type" IS NULL)) AND (products.archived <> true)
ORDER BY products.id
)
select t.*
from t
order by from_products_name
It seems to meet your requirements.
EDIT:
If the above does what you want, I can think of five options:
The above using a CTE.
Basically the same logic, using a subquery.
Using window functions, which is structurally very similar.
Using group by.
Using a where clause for the filtering logic.
Here is the group by method:
SELECT "products".*,
MIN(from_products_products.name) as from_products_name
FROM "products"
INNER JOIN "suppliers_plugin_source_products" ON "suppliers_plugin_source_products"."to_product_id" = "products"."id"
INNER JOIN "products" "from_products_products" ON "from_products_products"."id" = "suppliers_plugin_source_products"."from_product_id"
INNER JOIN "suppliers_plugin_source_products" "sources_from_products_products_join" ON "sources_from_products_products_join"."to_product_id" = "products"."id"
INNER JOIN "suppliers_plugin_suppliers" ON "suppliers_plugin_suppliers"."id" = "sources_from_products_products_join"."supplier_id"
WHERE "products"."profile_id" = 45781 AND (("products"."type" IN ('SuppliersPlugin::DistributedProduct') OR "products"."type" IS NULL)) AND (products.archived <> true)
GROUP BY products.id
ORDER BY from_products_name;
This form depends on products.id being declared as a primary key. Alternatively, you can put all the columns from that table in the group by.
Rewriting (simplifying the aliases) yields:
SELECT p1.*
FROM products p1
INNER JOIN suppliers_plugin_source_products spsp
ON spsp.to_product_id = p1.id
INNER JOIN products p2
ON p2.id = spsp.from_product_id
INNER JOIN suppliers_plugin_source_products spsp2
ON spsp2.to_product_id = p1.id -- <<-- Huh?
INNER JOIN suppliers_plugin_suppliers sps
ON sps.id = spsp2.supplier_id
WHERE p1.profile_id = 45781
AND (p1."type" IN ('SuppliersPlugin::DistributedProduct') OR p1."type" IS NULL)
AND p1.archived <> true
ORDER BY p2.name ASC -- <<-- Huh?
;
The outer query only refers to the product tables p1 and p2.
Assuming that JOINing the "suppliers_plugin_source_products" table twice was unintentional, this can be reduced to:
SELECT p1.*
FROM products p1
JOIN products p2
ON EXISTS (
SELECT * FROM suppliers_plugin_source_products spsp
-- the next line might not be necessary ...
INNER JOIN suppliers_plugin_suppliers sps ON sps.id = spsp.supplier_id
WHERE spsp.to_product_id = p1.id
AND spsp.from_product_id = p2.id
)
WHERE p1.profile_id = 45781
AND (p1."type" IN ('SuppliersPlugin::DistributedProduct') OR p1."type" IS NULL)
AND p1.archived <> true
ORDER BY p2.name ASC
;