Update database of a deployed web app - asp.net-mvc

Question

I'm using Entity Framework and I had to add some migrations. Now I'd like to update a customer's app and database.
I considered using update-database -script -SourceMigration migrationName command which doesn't work because I create a view in one of my migrations and it gives me the following exception in VS Console.
There is already an object named 'viewName' in the database.
It seems migrate.exe can be used too, but I'm not much familiar with its function and I prefer not to install anything on the customer's computer (because of limited access).
What's the best way to apply those migrations? I prefer to do it with a SQL script, but I can't get ride of that exception.
The migration code of the view:
public override void Up()
{
string script = #"CREATE VIEW [dbo].[viewName]
AS
SELECT *
FROM dbo.existingTable
WHERE (subquery)";
using (var db = new EFDbContext())
{
db.Database.ExecuteSqlCommand(script);
}
}
public override void Down()
{
var script = #"DROP VIEW [dbo].[viewName]";
using (var db = new EFDbContext())
{
db.Database.ExecuteSqlCommand(script);
}
}

Answer 1

The better way to add your views is using Sql inside Up and Down which ‘Up’ applies the changes to the target database and ‘Down’ reverts them:
public override void Up()
{
Sql("EXEC ('CREATE View [dbo].[viewName] AS --etc"
}
public override void Down()
{
Sql(#"IF EXISTS (SELECT
*
FROM sys.views
WHERE object_id = OBJECT_ID(N'dbo.viewName'))
DROP VIEW dbo.viewName)")
}