I am using SQL Server 2012.
I have three tables. Builders, Addresses and BuilderAddresses.
I have the following query which is used to give me my total count of records during paging:
SELECT COUNT(*) FROM Builders
LEFT JOIN Addresses ON Addresses.AddressId IN
(SELECT AddressId FROM BuilderAddresses WHERE BuilderId = Builders.BuilderId AND IsPrimary = 1)
WHERE Builders.[Email] LIKE '%TEST'%
ORDER BY Builders.[Name]
This query is particularly slow when records in the table approach 100k+. Does any one have any suggestions on how to get this query to execute faster??
On a table with 120K records, it take 452ms to get the count. When it comes to returning the records used in the paging, say 100 rows, it takes 11ms. I would really like to improve this if I can.
If I need to add greater detail, please let me know and I will edit the question.
The ORDER BY is not necessary for the COUNT, and you can remove that IN validation by joining with BuilderAdresses directly.
Try something like this:
SELECT COUNT(*)
FROM Builders b
LEFT JOIN BuilderAddresses ba ON ba.BuilderId = b.BuilderId AND isPrimary = 1
LEFT JOIN Addresses a ON a.AddressId = ba.AddressId
WHERE Builders.[Email] LIKE '%TEST' %
The problem is most likely to be with using IN as part of the join predicate. What it looks like you need to do is first join the junction table BuilderAddresses and then join Addresses, so something like this
SELECT COUNT(*) FROM Builders
JOIN BuilderAddresses ON BuilderAddresses.BuilderId = Builders.BuilderId AND isPrimary = 1
JOIN Addresses ON Addresses.AddressId = BuilderAddresses.AddressId
WHERE Builders.[Email] LIKE '%TEST%'
ORDER BY Builders.[Name]
Related
I'm trying to join some tables together, but when I join them the columns I am joining on are showing up separately.
My code looks something like this:
Select * FROM
SimulationOutput as SO
Inner Join SimulationInput as SI
ON SO.Key = SI.Key
AND
SO.Scenario = SI.Scenario
When I do this, I get the result I expected but my result also includes duplicates of The "Key" columns and the "Scenario" columns that I just joined on.
Is this expected behavior?
https://www.w3schools.com/sql/trysql.asp?filename=trysql_select_join_inner
On that website
I ran the following code:
Select * FROM
Orders
Inner Join Customers ON Orders.CustomerID = Customers.CustomerID
ORDER BY Orders.CustomerID
And in that output, the CustomerId column only shows up once, the Customers.CustomerID was dropped. I am trying to understand why this is happening in the latter, but not the former.
The reason I ask is because I intend to use a series of nested tables. And I'm running into duplicate column problems where SQL doesn't know which Scenario column to choose. I understand that I can specify the specific column, but I was planning on specifying my specific columns at the top fo the nested loop, and use a series of nested Select* in between.
So the structure would be something like
Select Column1, Column2, Column3 From
(Select * FROM ......
(Select * FROM.......
(Select * FROM..... ) as T1) as T2) as T3
I understand that this may not be ideal and for this question my end result is moot, I want to understand why the columns I'm joining on aren't being dropped the way they are on the w3schools website.
Is it because I am using an AND statement? Is there a better way to inner join using multiple criteria? Is it because of my version of SQL (TSQL?)
Image From W3 schools output
SELECT
c.ConfigurationID AS RealflowID, c.companyname,
c.companyphone, c.ContactEmail, COUNT(k.caseid)
FROM
dbo.Configuration c
INNER JOIN
dbo.cases k ON k.SiteID = c.ConfigurationId
WHERE
EXISTS (SELECT * FROM dbo.RepairEstimates
WHERE caseid = k.caseid)
AND c.AccountStatus = 'Active'
AND c.domainid = 46
GROUP BY
c.configurationid,c.companyname, c.companyphone, c.ContactEmail
I have this query - I am using the configuration table to get the siteid of the cases in the cases table. And if the case exists in the repair estimates table pull the company details listed and get a count of how many cases are in the repair estimator table for that siteid.
I hope that is clear enough of a description.
But the issue here is the count is not correct with the data that is being pulled. Is there something I could do differently? Different join? Remove the exists add another join? I am not sure I have tried many different things.
Realized I was using the wrong table. The query was correct.
I have 7 Tables as per attached following Image.
I will either enter Engine Number or Chassis Number and it should show the respective tables information (these tables have only mentioned fields) so all fields can be shown as result.
I can use hard coded Engine Number or Chassis Number. Every time of execution of this Query, I will hard code the required Engine/Chassis Number and will get the result.
Can anybody please help me to write this query for me?
Click Here to See the Tables
This might be a starting point for your solution.
SELECT prod.EngineNo AS engNo, prod.ChassisNo, doral.doralNo [, table.column [AS name]]
FROM DOProductSpecsDetais AS prod
INNER JOIN DORAL AS doral
ON prod.DOProductSpecsDetailID = doral.DOProductSpecsID
INNER JOIN DOProductDetail AS prodDetail
ON prod.DOProductDetailID = prodDetail.DOProductDetailID
WHERE prod.ChassisNo = '<input>' OR prod.EngineNo='<input>'
Between the SELECT and the FROM Statement, you can select any column out of your JOIN.
You can cascade as many JOINs as you like...
Which DBMS are you going to use?
One suggestion: Try to simplify the names of your columns, if possible.
One more: If you just started to do Database things, it is always helpful to start a test environment and use a client tool.
You can write query something like this:
select * from
DoProductSpecsDetail tbl1 inner join Doral tbl2
on tbl1.DoProductSpecsDetailId = tbl2.DoProductSpecsId
inner join DoproductDetail tbl3
on tbl1.DoProductDetailId = tbl3.DoProductDetailId
inner join ProductColor tbl4
on tbl1.ProductColorId = tbl4.ProductColorId
inner join DoDetail tbl5
on tbl3.DeliveryOrderDetailId = tbl5.DeliveryOrderId
inner join ProductMain tbl6
on tbl3.ProductId = tbl6.ProductId
inner join BPMain tbl7
on tbl5.BusinessPartnerId = tbl7.BusinessPartnerId
I just hit a wall with my SQL query fetching data from my MS SQL Server.
To simplify, say i have one table for sales, and one table for customers. They each have a corresponding userId which i can use to join the tables.
I wish to first SELECT from the sales table where say price is equal to 10, and then join it on the userId, in order to get access to the name and address etc. from the customer table.
In which order should i structure the query? Do i need some sort of subquery or what do i do?
I have tried something like this
SELECT *
FROM Sales
WHERE price = 10
INNER JOIN Customers
ON Sales.userId = Customers.userId;
Needless to say this is very simplified and not my database schema, yet it explains my problem simply.
Any suggestions ? I am at a loss here.
A SELECT has a certain order of its components
In the simple form this is:
What do I select: column list
From where: table name and joined tables
Are there filters: WHERE
How to sort: ORDER BY
So: most likely it was enough to change your statement to
SELECT *
FROM Sales
INNER JOIN Customers ON Sales.userId = Customers.userId
WHERE price = 10;
The WHERE clause must follow the joins:
SELECT * FROM Sales
INNER JOIN Customers
ON Sales.userId = Customers.userId
WHERE price = 10
This is simply the way SQL syntax works. You seem to be trying to put the clauses in the order that you think they should be applied, but SQL is a declarative languages, not a procedural one - you are defining what you want to occur, not how it will be done.
You could also write the same thing like this:
SELECT * FROM (
SELECT * FROM Sales WHERE price = 10
) AS filteredSales
INNER JOIN Customers
ON filteredSales.userId = Customers.userId
This may seem like it indicates a different order for the operations to occur, but it is logically identical to the first query, and in either case, the database engine may determine to do the join and filtering operations in either order, as long as the result is identical.
Sounds fine to me, did you run the query and check?
SELECT s.*, c.*
FROM Sales s
INNER JOIN Customers c
ON s.userId = c.userId;
WHERE s.price = 10
I am learning SQL (bit by bit!) trying to perform a query on our database and adding in a count function to show the total orders that appear against a customers id by counting in a inner join query.
Somehow it is pooling all the data together onto one customer with the count function though.
Can someone please suggest where I am going wrong?
SELECT tbl_customers.*, tbl_stateprov.stprv_Name, tbl_custstate.CustSt_Destination, COUNT(order_id) as total
FROM tbl_stateprov
INNER JOIN (tbl_customers
INNER JOIN (tbl_custstate
INNER JOIN tbl_orders ON tbl_orders.order_CustomerID = tbl_custstate.CustSt_Cust_ID)
ON tbl_customers.cst_ID = tbl_custstate.CustSt_Cust_ID)
ON tbl_stateprov.stprv_ID = tbl_custstate.CustSt_StPrv_ID
WHERE tbl_custstate.CustSt_Destination='BillTo'
AND cst_LastName LIKE '#URL.Alpha#%'
You need a GROUP BY clause in this statement in order to get what you want. You need to figure out what level you want to group it by in order to select which fields to add to the group by clause. If you just wanted to see it on a per customer basis, and the customers table had an id field, it would look like this (at the very end of your sql):
GROUP BY tbl_customers.id
Now you can certainly group by more fields, it just depends how you want to slice the results.
In your select statement you are using format like tableName.ColumnName but not for COUNT(order_id)
It should be COUNT(tableOrAlias.order_id)
Hope that helps.
As you are new to SQL it might also be worth considering the readability of your joins - the nested / bracketed joins you mentioned above are quite hard to read, and I would also personally alias your tables to make the query that bit more accessible:
SELECT
tbl_customers.customer_id
,tbl_stateprov.stprv_Name
,tbl_custstate.CustSt_Destination
,COUNT(order_id) as total
FROM tbl_stateprov statep
INNER JOIN tbl_custstate state ON statep.stprv_ID = state.CustSt_StPrv_ID
INNER JOIN tbl_customers customer ON customer.cst_ID = state.CustSt_Cust_ID
INNER JOIN tbl_orders orders ON orders.order_CustomerID = state.CustSt_Cust_ID
WHERE tbl_custstate.CustSt_Destination='BillTo'
AND cst_LastName LIKE '#URL.Alpha#%'
GROUP BY
tbl_customers.customer_id
,tbl_stateprov.stprv_Name
,tbl_custstate.CustSt_Destination
--And any other columns you want to include the count for