Is it possible to run native sql with entity framework?

Question

I am trying to search an XML field within a table, This is not supported with EF.

Without using pure Ado.net is possible to have native SQL support with EF?

Answer 1

Since .NET 4 you can use ExecuteStoreQuery method:

var list = myDBEntities.ExecuteStoreQuery<MyClass>(MyClass.sql);

where myDBEntities is inherited from ObjectContext.

class MyClass
{
    /* You can change query to more complicated, e.g. with joins */
    public const string sql = @"select [MyTable].[MyField] from [MyTable]";
    public string MyField { get; set; }
}

Notice that MyTable is real table name, not EF class.

Answer 2

Using Entity Framework 5.0 you can use ExecuteSqlCommand to execute multi-line/multi-command pure SQL statements. This way you won't need to provide any backing object to store the returned value since the method returns an int (the result returned by the database after executing the command).

Sample:

context.Database.ExecuteSqlCommand(@
"-- Script Date: 10/1/2012 3:34 PM  - Generated by ExportSqlCe version 3.5.2.18
SET IDENTITY_INSERT [Students] ON;

INSERT INTO [Students] ([StudentId],[FirstName],[LastName],[BirthDate],[Address],[Neighborhood],[City],[State],[Phone],[MobilePhone],[Email],[Enrollment],[Gender],[Status]) VALUES (12,N'First Name',N'SecondName',{ts '1988-03-02 00:00:00.000'},N'RUA 19 A, 60',N'MORADA DO VALE',N'BARRA DO PIRAÍ',N'Rio de Janeiro',N'3346-7125',NULL,NULL,{ts '2011-06-04 21:25:26.000'},2,1);

INSERT INTO [Students] ([StudentId],[FirstName],[LastName],[BirthDate],[Address],[Neighborhood],[City],[State],[Phone],[MobilePhone],[Email],[Enrollment],[Gender],[Status]) VALUES (13,N'FirstName',N'LastName',{ts '1976-04-12 00:00:00.000'},N'RUA 201, 2231',N'RECANTO FELIZ',N'BARRA DO PIRAÍ',N'Rio de Janeiro',N'3341-6892',NULL,NULL,{ts '2011-06-04 21:38:38.000'},2,1);
");

For more on this, take a look here: Entity Framework Code First: Executing SQL files on database creation

Answer 3

public class RaptorRepository<T>
    where T : class
{
    public RaptorRepository()
        : this(new RaptorCoreEntities())
    {
    }

    public RaptorRepository(ObjectContext repositoryContext)
    {
        _repositoryContext = repositoryContext ?? new RaptorCoreEntities();
        _objectSet = repositoryContext.CreateObjectSet<T>();
    }

    private ObjectContext _repositoryContext;
    private ObjectSet<T> _objectSet;
    public ObjectSet<T> ObjectSet
    {
        get
        {
            return _objectSet;
        }
    }


    public void DeleteAll()
    {
        _repositoryContext
            .ExecuteStoreCommand("DELETE " + _objectSet.EntitySet.ElementType.Name);
    }
}

Answer 4

So what do we say about all this in 2017? 80k consultations suggests that running a SQL request in EF is something a lot of folk want to do. But why? For what benefit?

Justin, a guru with 20 times my reputation, in the accepted answer gives us a static method that looks line for line like the equivalent ADO code. Be sure to copy it well because there are a few subtleties to not get wrong. And you're obliged to concatenate your query with your runtime parameters since there's no provision for proper parameters. So all users of this method will be constructing their SQL with string methods (fragile, untestable, sql injection), and none of them will be unit testing.

The other answers have the same faults, only moreso. SQL buried in double quotes. SQL injection opportunities liberally scattered around. Esteemed peers, this is absolutely savage behaviour. If this was C# being generated, there would be a flame war. We don't even accept generating HTML this way, but somehow its OK for SQL. I know that query parameters were not the subject of the question, but we copy and reuse what we see, and the answers here are both models and testaments to what folk are doing.

Has EF melted our brains? EF doesn't want you to use SQL, so why use EF to do SQL.

Wanting to use SQL to talk to a relational DB is a healthy, normal impulse in adults. QueryFirst shows how this could be done intelligently, your sql in .sql file, validated as you type, with intellisense for tables and columns. The C# wrapper is generated by the tool, so your queries become discoverable in code, with intellisense for your inputs and results. End to end strong typing, without ever having to worry about a type. No need to ever remember a column name, or its index. And there are numerous other benefits... The temptation to concatenate is removed. The possibility of mishandling your connections also. All your queries and the code that accesses them are continuously integration-tested against your dev DB. Schema changes in your DB pop up as compile errors in your app. We even generate a self test method in the wrapper, so you can test new versions of your app against existing production databases, rather than waiting for the phone to ring. Anyone still need convincing?

Disclaimer: I wrote QueryFirst :-)

Answer 5

For Entity Framework 5 use context.Database.SqlQuery.

And for Entity Framework 4 use context.ExecuteStoreQuery the following code:

 public string BuyerSequenceNumberMax(int buyerId)
    {
        string sequenceMaxQuery = "SELECT TOP(1) btitosal.BuyerSequenceNumber FROM BuyerTakenItemToSale btitosal " +
                                  "WHERE btitosal.BuyerID =  " + buyerId +
                                  "ORDER BY  CONVERT(INT,SUBSTRING(btitosal.BuyerSequenceNumber,7, LEN(btitosal.BuyerSequenceNumber))) DESC";

        var sequenceQueryResult = context.Database.SqlQuery<string>(sequenceMaxQuery).FirstOrDefault();

        string buyerSequenceNumber = string.Empty;

        if (sequenceQueryResult != null)
        {
            buyerSequenceNumber = sequenceQueryResult.ToString();
        }

        return buyerSequenceNumber;
    }

To return a List use the following code:

 public List<PanelSerialList> PanelSerialByLocationAndStock(string locationCode, byte storeLocation, string itemCategory, string itemCapacity, byte agreementType, string packageCode)
 {
       string panelSerialByLocationAndStockQuery = "SELECT isws.ItemSerialNo,  im.ItemModel " +
        "FROM Inv_ItemMaster im   " +
        "INNER JOIN  " +
        "Inv_ItemStockWithSerialNoByLocation isws  " +
        "   ON im.ItemCode = isws.ItemCode   " +
        "       WHERE isws.LocationCode = '" + locationCode + "' AND  " +
        "   isws.StoreLocation = " + storeLocation + " AND  " +
        "   isws.IsAvailableInStore = 1 AND " +
        "   im.ItemCapacity = '" + itemCapacity + "' AND " +
        "   isws.ItemSerialNo NOT IN ( " +
        "           Select sp.PanelSerialNo From Special_SpecialPackagePriceForResale sp  " +
        "           Where sp.PackageCode = '" + packageCode + "' )";


    return context.Database.SqlQuery<PanelSerialList>(panelSerialByLocationAndStockQuery).ToList();


}

Answer 6

Keep it simple

using (var context = new MyDBEntities())
{
    var m = context.ExecuteStoreQuery<MyDataObject>("Select * from Person", string.Empty);
    //Do anything you wonna do with 
    MessageBox.Show(m.Count().ToString());
}