SQL Server :: Slow Running Query Based On Multiple Tables Using Joins
Nov 15, 2010
One of my peer wrote a query based on multiple tables using joins. One of the table is in a different database The query was taking much time
1. Create an SP
2. Create a temp table and copy all records from the external db
3. Avoid using Left Join as much as possible and use Inner Join
4. Create and use indexes
5. Remove tables/columns that are not necessary
In this scenario, I would like to suggest to use Covering Index, but how can it be created for multiple tables and a temp table?
The below SQL query is running extremely slow. Im using this query on other tables and its processing about 5 rows per second. The below version is running 1 row every 10 seconds when @SQLNew is executed.
I have one question regarding how to make the below mentioned type of query more optimized so that mine query perfomace can be increased.
Select a.name1,a.address1,b.field3,c.field4,d.field6,e.field7 from a inner join b on a.id=b.id inner join c on c.id=b.id inner join d on d.id=c.id iner join e on e.id=d.id union all Select a1.name1,a1.address1,b1.field3,c.field4,d.field6,e.field7 from a1 inner join b1 on a1.id=b1.id inner join c on c.id=b1.id inner join d on d.id=c.id iner join e on e.id=d.id union all Select a2.name1,a2.address1,b2.field3,c.field4,d.field6,e.field7 from a2 inner join b2 on a2.id=b2.id inner join c on c.id=b2.id inner join d on d.id=c.id iner join e on e.id=d.id
All the above three select query at last using the same inner join condition, means last two inner join condition are the same for all the select query.
Is there any way so that this query can be optimized?
Inner Join:- Returns a row when there is matching table in both tables. we can use comparison operator like =,<,>,<>
I created two tables
TableA
ID OID Type
1 1 A 2 6 B 3 7 C 4 10 D
TableB
ID Value 1 10 2 30 3 40 5 60 6 70
Basic Inner Join select Type From TableB as a inner join TableA as b on a.ID=b.OID Result Type
A B
If i want only the type which has not match in tableB then i can use not in subquery i get the result if i m using select Type From TableB as a inner join TableA as b on a.ID<>b.OID then i get
Is there a way to select data from multiple tables other than the UNION ALL statement. Addtionally I need to select data from a different database.
My current statement is as follows (there are alot more fields but I have shortened it ):
SELECT server.dbo.SRFILE.SR_GROUP, server.dbo.SRFILE.SROWNERSHIP, server.dbo.SRFILE.SRCONMAE, BSFLBWF_1.Incidentx, BSFLBWF_1.Severityx FROM server.dbo.SRFILE INNER JOIN BSFLBWF AS BSFLBWF_1 ON BSFLBWF_1.Incidentx = server.dbo.SRFILE.SRONUMBER WHERE (BSFLBWF_1.Closex IS NULL).........
I am trying to display this query result in an aspx page.
It is very slow in loading. Here is the query. The inner query inside the outer quesry is the problem.(Please see the underlined part in the query) - (If I remove that part it is very fast.)
select
top 500
--This column is the issue ,Governing_Class=( case when exists (select top 1 tqc.class_code from t_quote_class tqc inner join t_quote_class_premium tqcm on tqc.class_code =tqcm. class_code where tqc.appid=pi.appid and tqc.class_code not in('8742' ,'8810','7380') order by tqcm.premium_amt desc ) then ( select top 1 tqc.class_code from t_quote_class tqc inner join t_quote_class_premium tqcm on tqc.class_code =tqcm. class_code where tqc.appid=pi. appid order by tqcm.premium_amt desc ) ......... From tables
A follow up question concerning the DAL layer part .. The first question about dealing with large objectsI have one table (PlacesTable) that is connected by like 6 other tables (1:Many and Many:Many relations)
In my DAL should I put a big query that join the 6 tables + the m:m reference tables (btw it produces multiple data that I don't need Please refer to my old question) and place all the data in it's specific object property or, should I use a single query for each table and create an object for each fetched table .. and finally send those to the UI ?If I wasn't clear enough please let me know what I further information do you need to know!
I'm facing a problem in our current running application. There is a table in database which has 67 columns,among these 18 columns are nvarchar(max) datatype and contains 30K records. Problem is now that SELECT * FROM myTable it takes around 3 to 4 seconds. Which is degrading our application's performance.
have a database and I've created a DBML Linq-to-SQL file to represent this database. I've created a new aspx page and dropped a linqdatasource and a formview control onto it. When I configure the linqdatasource it gives me the choice only to select * from one table...but I want to pull from multiple tables. e.g. I have tables like simple_person, simple_address, simple_phone, and I want to pull from all of them.
I've got this query UPDATE linkeddb...table SET field1 = 'Y' WHERE column1 = '1234' This takes 23 seconds to select and update one row But if I use openquery (which I don't want to) then it only takes half a second.
The reason I don't want to use openquery is so I can add parameters to my query securely and be safe from SQL injections. Does anyone know of any reason for it to be running so slowly?
The gist of the problem is that we have an alumni table (one record per person) and also a couple of other tables (one to many) that have degree info and interest info. In a search screen in our app you can search for criteria that spans all three tables (there are actually more fields and tables than shown in the example below but I am trying to keep it simple).
The code below works (properly returns people without degrees for example) but still feels a little clunky or over-engineered to me. Are there easier ways to do this? NOTE: I have been through quite a few iterations/approaches to making the correct data be returned.
I am writting a directory website that advertises fitness classes. These classes are listed by Class Type, and Geographical Area. Each Class Type can satisfy one or more of four Fitness Goals such as Loose Weight etc...
I have a table for Classes (classid, classname, classdesc, classtypeid, geoareaid) I have a table for geographic areas (geoareaid, geoarea) And I have a table for ClassTypes (classtypeid, classtypename, classtypedesc)
Which obviously links geographic area via the classes.geoareaid as a forgien key and classtypes by classes.classtypeid as a forgien key.
I can list all classes by type and also by geo area no problem, the problem arrises when I then also want to filter by goal.
The Goals Table (goalid, goal, goaldesc) is linked to the classtypes table via another table classtypes_goals (classtypeid, goalid) as each classtype can satisfy any of the 4 goals.
I am using a DataSet to fetch the data from a Stored Procedure in the SQL Database but because the classtypes can be linked to multiple goals I am getting duplication in my list depending on how many goals a classtype satisfies.
All I need in my data list is class name, class type and area I don't even need to display the goal I just want a drop down above the table that will filter the list and show only classes of classtype that satisfy the goal chosen.
Here's the scenario: Buyers and Sellers (where all of the sellers have a unique D&B number).
I'm catering to the buyers, and I want them to be able to import a list of sellers based on the D&B number.
Here are the tables:
BuyersSellers - unique list of sellers - one record, no matter how many buyers work with them.BuyerSellers - lookup table - buyer_id, seller_id sets which buyers work with which sellers ImportedSellers - temp table that holds sellers the buyer wants to add.AllSellers - master table that has all known sellers with D&B numbers (remote database).
Here's the process:
Buyer uploads list of new sellers, they get added to ImportSellers tableMatch ImportedSellers against AllSellers (valid), ignore unmatched (invalid).Add valid ImportedSellers to the Sellers table if they don't exist.Create BuyerSeller records for all valid ImportedSellers - using data from AllSellers.Delete all valid ImportedSellers, leave the unmatched behind so they know what they need to fix.
I've got the upload and import working, but now I'm a little stuck on how to do all of the matching and inserting, and do it as quickly as possible.
how can I display a linq query in a gridview that has data from multiple tables AND allow the user to edit some of the fields or delete the data from a single table?
I'd like to do this with either a linqdatasource or a linq query. I'm aware I can set the e.Result to the query on the selecting event. I've also been able to build a custom databound control for displaying the linq relations (parent.child).
However, I'm not sure how I can make this work with delete? I'm thinking I may need to handle the delete event with custom code.
I have a view that has to render information from 3-4 tables. I therefore chose to create a viewModel for this. I am using EF as DAL.The information to be displayed is SiteId, SiteName, SiteDetails from one table.Associated to Site, other table Event_type has information about Events in the system with fileds like EventId, EventName, Event ScopeId.EventScope is another table with ScopeID and ScopeDesc Also, there is Site_Event_Implemnetation table that stores all the events associated to a site. It has SiteId, EventId, EventUnitIdEventUnit is another table that stores all the unit types.Now my Details ViewModel has to display the info SiteName, SiteDetails. And associated to that a grid of events with info on EventName, Scope Desc, Unit Desc1. How do I formulate my query to retrieve this info in my repository layer using Linq to EF?
In my database when I fire query it takes 40 secs on 1 crore data, similar when I use join with other table then it take more time. I have taken care non cluster index such thing. But still I want to optimize my query, what other thing I need to take like buffer, disk size etc. I am not sure on this area.
I have some problems trying to query my database. The problem is that I'm not sure how to multiple join tables in my database.
tables to make it easier:
[code]....
What I'm supposed to do is to find all the teachers (predavac) who were teachers on the specific activity (aktivnost) and who had specific attendee (polaznik). The problem is I'm not sure how to do multiple joins on this one.
I am running a sql script which Inserts 500 rows and after each insert, it calls a stored procedure which diplays result in the results window. So after executing 100 rows, it throws an error that maximum number od results in the results pane has reached its limit but the query executes successfully. How can we disable the stored proc output to not display in the results pane. I do not have access to the stored procedure.
I am a little new to this concept so bear with me.1) I need to query atleast 35 tables using linq to sql(SQL server database) . I am not able to add all the database entities in Linq to sql classes?
2)(View Model issue) When I use List<Reportcollection> and also List<Receipt> to convert the result then its giving an error that "Cannot convert list<anonymous> to list<string>"
Here I'm using three tables given below. As u can see in the below three tables, 3 columns(P_Id,PdtName,PdtImgUrl) are same. Now can any body tell me how can I retreive values of 3 columns(P_Id,PdtName,PdtImgUrl) without repeatition.
I'm more into the LAMP stack, but I've been asked to work on a site that is running Windows and IIS 2008. I'm a beginner with IIS, so please be patient with me on this, and please ask me to provide more information if that is needed to determine. I read the answer here (Slow first page load on asp.net site), but it seems like if I go to the site with one browser it takes long to load the first page, then fast on all other pages, then if I open up another browser, it's the same thing, so it's not something that is saved on the server, but per session? Is there a way to have the application running at all times? Right now it is taking 12 to 15 seconds for the first page to load. I have access to the WebControlCenter and FTP.
There's a web app I've been assigned to, which is running very slow. It is a site that sells products so it is database driven, however even pages that do not query the database are loading very slow. The pages use master pages, and the code is in VB.NETI checked with fiddler and the time it takes to load basic (non database driven) pages are about 5.5 seconds on average.
What are some tools that can help me determine the cause of the slow speeds, and any recommendations as to how to speed it up, or potential issues that could cause it?UpdateSo I messed around with the code piece by piece as I wasn't getting anywhere with these tools. As soon as I remove master pages, and I include the same code that's on the master pages in the .aspx page itself, the speed improves drastically (approximately 5 times faster load times).What might cause the master pages to cause load times to slow down so much?
I am accessing rows in an SQL database table based upon the contents of the Primary key and another column. But, I cannot insert new rows in the table when the content of the new Primary key column already exists in another row. Can I define the table with a multiple column Primary key so that a unique value can be based upon the content of both columns?
