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Is it any opportunity to set label to query in EF?

I'm using Entity Framework to generate sql queries. And DB admins send me queries which are too slow or not optimized. But in app are hundreds requests to DB and too hard to find right one.
Is it any possibilities to set label in query? I need it to find query faster than I do it now.

depends a little on your EF version ...
in EF6 for example you could take the command interception approach to modify all SQL statements EF generates ...
see https://www.entityframeworktutorial.net/entityframework6/database-command-interception.aspx

Can Entity Framework generate an UPDATE ... WHERE statement in SQL?

Building a data access layer for an internal enterprise MVC application with Entity Framework and the repository pattern. In some cases, I need to update, say, 100k rows in a table with 100 million or so rows in a SQL Server 2008 R2 database.
I am using EF6, targeting an existing legacy database we are refactoring. I am new to Entity Framework, but have much experience with SQL Server.
No matter how I seem to structure my update statement, when I run a profiler, I see 60k individual updates by ID. This can take up to 5 minutes to run. However, I have say a "batch number" that is indexed for a bunch of these records. Is there any way to UPDATE these records with a single where clause generated from EF? My solution has been to just write a simple sp that I then have EF call.

Entity Framework in its current version does not support bulk operations in the sense that you are wanting it to. Each update or delete will be one individual transaction per record. To avoid this, you can run SQL directly from Entity Framework if you do not want to go through the hassle of creating a stored procedure (though, they are pretty easy to get up and going)
using (var context = new MyDbContext())
{
context.ExecuteStoreCommand("Update MyTable Set Value = {0} Where SomeColumn = {1}",
updateValue, queryValue);
context.ExecuteStoreCommand("Delete From MyTable Where value = {0}",
myValueToQueryBy);
}
Note the use of the parameter by using syntax that looks very similar to a string.Format(). Please see the MSDN for more information.

Executing custom sql including complex select joins using entity framework 4

My application currently uses ado.net to access the database.
It allows users to configure dashboards by passing custom sql. The custom sql includes joins on multiple tables and the columns of every table are included in the result.
We are migrating from ado.net to entity framework 4.
How do I execute the same queries using entity framework?
Also other code in the application requires firing custom complex join queries on the database. This is done by developers.

Yes you can use inline queries and even stored procedue in entityframework
see example for query http://msdn.microsoft.com/en-us/library/bb738451
see example for stored procedure http://msdn.microsoft.com/en-us/library/bb896334.aspx

If you have dynamic queries you cannot execute them through EF. EF works in strongly typed manner so it expects that you created the type with correct properties (with correct types) at design time (you can create the type at runtime as well but it requires you to create dynamic assembly, emit IL, etc.).
Use your old approach for this type of queries.

Entity framework run direct query

I'm thinking about using Entity Framework in an ASP.NET application, using an Oracle database.
I would also need to know is I can run a query directly on the database tables and data, using Entity Framework, without using the classes and the mappings.
Thanks!

ExecuteStoreQuery can be used.
However, part of the beauty/fun/elegance of using Entity is being able to write your queries using LINQ and not having to write actual SQL statements.
Also, just because you decide to use Entity, doesn't mean you can no longer use SqlCommand objects etc...

You could use ExecuteStoreQuery() for that. Be aware though that you a have to provide a type that all returned columns can be mapped to, it does not have to be an entity though.

Loading SQL tables using Entity Framework

I want to use Entity Framework to a load a number of sql tables into memory from my c# app before performing some work on them and sending changes back to the database. I only want to hit the database once when I load the data and once more when I update changes. Should I load the tables into a dataset or is there a better way to achieve this?

In such case you can't use entity framework. Entity framework will hit database for once for loading each table (unless there are relations which can load all tables in single query as #Jakub suggested) and it will hit database for each performed change. EF doesn't have command batching and each modified, inserted or deleted entity will cause separate roundtrip to DB.

Turn off lazy loading or use Include() to specify related entities that should be loading in a single query.
If you're using CTP5 look here: http://blogs.msdn.com/b/adonet/archive/2011/01/31/using-dbcontext-in-ef-feature-ctp5-part-6-loading-related-entities.aspx