How to execute raw SQL query using Entity Framework without having to use a model?

Question

I am trying to learn C# ASP.NET MVC 5. And I am trying to use Entity Framework for everything I do.

However, I need to run a raw SQL query and return the results into an array.

Here is what I have done so far.

I created my context class which allows me to connect to a server and it also allows me to change the database at run time.

Here is my context class

using ScripterEngine.Models; using System; using System.Collections.Generic; using System.Data.Common; using System.Data.Entity; using System.Data.Entity.Core.EntityClient; using System.Data.SqlClient; using System.Linq; using System.Web;  namespace ScripterEngine.DataAccessLayer {     public class BaseContext : DbContext     {         protected string connectionName;         public DbSet<Campaign> Campaign { get; set; }          /**          * Created the connection to the server using the giving connection string name          *           * @param connName          */         public BaseContext(string connName = "BaseConnection")             : base(connName)         {             connectionName = connName;         }          /**          * Changes the default database          *           * @param databaseName          */         public BaseContext setDatabase(string databaseName)         {             var connectionString = System.Configuration.ConfigurationManager.ConnectionStrings[connectionName].ConnectionString;              SqlConnectionStringBuilder builder = new SqlConnectionStringBuilder(connectionString);              //change the database before creating the new connection             builder.InitialCatalog = databaseName;              string sqlConnectionString = builder.ConnectionString;              return new BaseContext(sqlConnectionString);         }     } } 

And how to make the connection here is what I do

BaseContext db1 = new BaseContext("server1"); var db1New = db1.setDatabase("someTableName"); string tableName = "SomeTableName";  var results = db1New.Database.SqlQuery("SELECT LOWER(column_name) AS column_name FROM information_schema.columns WHERE table_name = @tableName", tableName).ToArray(); 

This throws an error

The type arguments for method 'System.Data.Entity.Database.SqlQuery(string, params object[])' cannot be inferred from the usage. Try specifying the type arguments explicitly. C:.NET Projects\ScripterEngine\ScripterEngine\Controllers\CampaignController.cs 42 27 ScripterEngine

How can I execute this raw query?

Answer 1

Specify string as the type argument.

var results = db1New.Database.SqlQuery<string>("SELECT LOWER(column_name) AS column_name FROM information_schema.columns WHERE table_name = @p0", tableName).ToArray();                                        ^^^^^^