public void AddFeed(DAL.Feed feed)
{
//The AUTOINCREMENT keyword imposes extra CPU, memory, disk space, and disk I/O overhead and should be avoided if not strictly needed.
//It is usually not needed.
//On an INSERT, if the ROWID or INTEGER PRIMARY KEY column is not explicitly given a value, then it will be filled automatically with an unused integer, usually one more than the largest ROWID currently in use.
//This is true regardless of whether or not the AUTOINCREMENT keyword is used.
//In Entity Framework, the SaveChanges() method internally creates a transaction and wraps all INSERT, UPDATE and DELETE operations under it.
//Multiple SaveChanges() calls, create separate transactions, perform CRUD operations and then commit each transaction.
using (var context = new ORM.Entities())
{
//context.Database.Log = Console.Write;
long maxid = context.Feeds.Max(f => f.Id);
ORM.Feed f = new ORM.Feed()
{
Id = maxid + 1,
Name = feed.Name,
Url = feed.Url,
Xml = feed.Xml
};
context.Feeds.Add(f);
context.SaveChanges();
feed.Id = f.Id;
}
}
public void DeleteFeed(long id)
{
using (var context = new ORM.Entities())
{
ORM.Feed dbFeed = context.Feeds.FirstOrDefault(f => f.Id == id);
if (dbFeed == null)
{
throw new Exception($"Feed {id} not found in repository.");
}
context.Feeds.Remove(dbFeed);
context.SaveChanges();
}
}
public void UpdateFeed(DAL.Feed feed)
{
//var f = new ORM.Feed() { Id = feed.Id, Name = feed.Name, Url = feed.Url };
//using (var context = new ORM.Entities())
//{
// context.Feeds.Attach(f);
// context.Entry(f).Property("Name").IsModified = true;
// context.Entry(f).Property("Url").IsModified = true;
// context.SaveChanges();
//}
using (var context = new ORM.Entities())
{
ORM.Feed dbFeed = context.Feeds.FirstOrDefault(f => f.Id == feed.Id);
if (dbFeed == null)
{
throw new Exception($"Feed {feed.Id} not found in repository.");
}
dbFeed.Name = feed.Name;
dbFeed.Url = feed.Url;
dbFeed.Xml = feed.Xml;
context.SaveChanges();
}
}