Prevent LinqPad from querying __MigrationHistory - entity-framework

Question

This is about a performance optimization:
I use LinqPad to access a database using an EF 6 DbContext. The database is created using code first.
When I run a query, I see the correct result, but I see in the "SQL"-tab that LinqPad (and/or EF) emmits SQL to check the migration history:
-- Region Parameters
-- p__linq__0: String [UserQuery]
-- EndRegion
SELECT
"GroupBy1".A1 AS C1
FROM ( SELECT Count(1) AS A1
FROM ARIANE_ADMIN."__MigrationHistory" "Extent1"
WHERE "Extent1"."ContextKey" = :p__linq__0
) "GroupBy1"
GO
-- Region Parameters
-- p__linq__0: String [UserQuery]
-- EndRegion
SELECT
"GroupBy1".A1 AS C1
FROM ( SELECT Count(1) AS A1
FROM "__MigrationHistory" "Extent1"
WHERE "Extent1"."ContextKey" = :p__linq__0
) "GroupBy1"
GO
SELECT
"GroupBy1".A1 AS C1
FROM ( SELECT Count(1) AS A1
FROM "__MigrationHistory" "Extent1"
) "GroupBy1"
GO
SELECT
"Extent1"."Id",
"Extent1"."ModelHash"
FROM "EdmMetadata" "Extent1"
ORDER BY "Extent1"."Id" DESC
FETCH FIRST 1 ROWS ONLY
GO
Only then there is the actual query.
Since I usually access the DB through multiple layers of VPN, the extra queries cost more than a second.
My questions are:
Can I avoid the query to '__MigrationHistory' alltogether?
If not: Is there a way to pass the correct parameter instead of '[UserQuery]', so that the first query returns the correct result?
I connect to an Oracle server using Devart dotconnect for Oracle.

Answer 1

As Steve Greene suggested, you have to set a null initializer. But not for your DbContext. It must be set for the UserQuery-Type that LinqPad dynamically creates.
It can be done by writing
Database.SetInitializer<UserQuery>(null);
at the beginning of every LinqPad query.
A more general approach is to set it in your dll using reflection.
Add this extension method
public static class DbContextExtensions
{
public static void RemoveLinqpadInitializer(this DbContext context)
{
var contextType = context.GetType();
if (contextType.Name == "UserQuery")
{
var setInitializer = typeof(Database).GetMethod(nameof(Database.SetInitializer))?.MakeGenericMethod(contextType);
setInitializer?.Invoke(null, new object[] {null});
}
}
}
and call it in your DbContext:
public class MyDbContext : DbContext
{
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
Database.SetInitializer<MyDbContext>(null); // or any other initializer
this.RemoveLinqpadInitializer();
}
}