public void SaveTest()
{
using (var db = new ASP_DBEntities())
using (var trans = db.Database.BeginTransaction(IsolationLevel.ReadUncommitted))
{
try
{
// 1. Write
var session = Guid.NewGuid();
var now = DateTime.Now;
var main = new Main();
main.session = session;
main.created = now;
main.changed = now;
main.main = new byte[0];
db.Main.Add(main);
db.SaveChanges();
// 2. Read
var query = from m in db.Main
where m.session == session
select m;
var read = query.FirstOrDefault();
Assert.That(main.created, Is.EqualTo(now));
}
finally
{
trans.Rollback();
}
}
}
public void SaveUpdateTest()
{
const int DB_ROUNDTRIP_MILLISECONDS = 500;
using (var db = new ASP_DBEntities())
using (var trans = db.Database.BeginTransaction(IsolationLevel.ReadUncommitted))
{
try
{
var main = new Main();
db.Main.Add(main); // add incomplete object, possible unlike with Strongly Typed Datasets
main.main = new byte[3] {
1, 2, 3
};
// INSERT: read back inserted and computed values
db.SaveChanges();
var insertedAt = DateTime.Now;
Assert.Multiple(() => // direct assertions on the model object
{
Assert.That(main.main, Is.EqualTo(new byte[3] {
1, 2, 3
}));
Assert.That(main.created, Is.EqualTo(main.changed)); // exact time from the db
Assert.That(main.changed, Is.EqualTo(insertedAt).Within(DB_ROUNDTRIP_MILLISECONDS).Milliseconds); // db rounttrip time
});
// UDPATE: read back updated and computed values
Thread.Sleep(500); // greater than db roundtrip time
main.main = new byte[3] {
4, 5, 6
};
db.SaveChanges();
var createdAt = main.created; // exact time from the db
var changedAt = DateTime.Now;
Assert.Multiple(() => // direct assertions on the model object
{
Assert.That(main.main, Is.EqualTo(new byte[3] {
4, 5, 6
}));
Assert.That(main.created, Is.EqualTo(createdAt));
Assert.That(main.changed, Is.GreaterThan(main.created));
Assert.That(main.changed, Is.EqualTo(changedAt).Within(DB_ROUNDTRIP_MILLISECONDS).Milliseconds);
});
// DELETE: delete with initially detached object
var session = main.session;
var detached = new Main {
session = session
};
db.Main.Attach(main); // must exist, otherwise SaveChanges() throws an exception
db.Main.Remove(main);
db.SaveChanges();
this.TestReadInexistent(db, session);
}
finally
{
trans.Rollback();
}
}
}
