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Entity Framework v6 GroupBy Losing Original Ordering


Entity Framework v6 GroupBy Losing Original Ordering

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Entity Framework v6 GroupBy Losing Original Ordering
Tag : entity-framework , By : 小和尚
Date : December 01 2020, 05:00 PM

hop of those help?
I expect for it to order the vehicles by RangeId and then by rental
SELECT Brand, COUNT(*) 
FROM Cars
GROUP BY Brand
var results = queryBuilder
              .GroupBy(x => x.Vehicle.RangeId)
              .Select(x => x.OrderBy(o => o.Rate.Rental).FirstOrDefault())
              .Select(o => new { o.Rate.Rental, o }
              .AsEnumerable()
              .OrderBy(x => x.Rental);

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Can I specify child entity default ordering with Entity Framework Code First?


Tag : chash , By : Fenix Drakken
Date : March 29 2020, 07:55 AM
With these it helps You must write a query for that. Ordering is not managed by mapping.

How to get original values of an entity in Entity Framework?


Tag : development , By : Thomas Gueze
Date : March 29 2020, 07:55 AM
Does that help You can access them through ObjectStateEntry
var originalValues = context
         .ObjectStateManager.GetObjectStateEntry(myEntity).OriginalValues;

Losing responsiveness when using Entity Framework


Tag : chash , By : Jesenko Mehmedbasic
Date : March 29 2020, 07:55 AM
may help you . All the code is executed in the UI thread in your case, because the Control.BeginInvoke method is not supposed to run a delegate in a background thread. To execute the code asynchronously, use the BeginInvoke method of a delegate. For example:
private void async_fillgridwithdatatable(DataGridView grid, DataTable table)
{
    Func<DataTable, IEnumerable<string>> action = new Func<DataTable, IEnumerable<string>>(UpdateDbAndGetData);
    action.BeginInvoke(o => grid.Invoke(new Action<IEnumerable<string>>(rows => {
                                grid.Rows.Clear();
                                foreach (string username in rows)
                                    grid.Rows.Add(username);    
                            }), 
        action.EndInvoke(o)));
}

IEnumerable<String> UpdateDbAndGetData(DataTable table) {
    var existing = db.GetMemberList();
    foreach (DataRow row in table.Rows)
    {
        var username = row["Q51_1"].ToString();
        if (!existing.Contains(username))
        {
            MyDirHelper ldap = new MyDirHelper(username, "");
            int acclvl = ldap.GetAccessLevel();
            tbl_Member newMember = new tbl_Member
                {
                    username = username,
                    first_name = row["Q9_1"].ToString(),
                    last_name = row["Q9_2"].ToString(),
                    .
                    .
                    .
                    id_accesslevel = db.DB_GetMemberAutoAccessLevelIDByLDAPAccessLevel(acclvl),
                    created_on = DateTime.Now,
                    created_by = db.GetUser(E_Username).id_user,
                    modified_by = db.GetUser(E_Username).id_user,
                    modified_on = DateTime.Now
                };
            db.InsertIntoMembersEntity(newMember);
            if (newMember.id_accesslevel != 1)
            {
                if (newMember.id_accesslevel != null)
                {
                    mail_sendWelcome(newMember.email, newMember.id_accesslevel.Value);
                    db.UpdateMemberWelcomeMailSentDate(newMember.id_member, DateTime.Now);
                }
            }
        }
        else
        {
            tbl_Member existingMember = db.GetMemberByLogin(username);

                    existingMember.first_name = row["Q9_1"].ToString();
                    existingMember.last_name = row["Q9_2"].ToString();
                    .
                    .
                    .
                    existingMember.modified_by = db.GetUser(E_Username).id_user;
                    existingMember.modified_on = DateTime.Now;

            db.Save();
        }
        yield return username;
    }
}

Implementation of List<T> is losing the ordering on the original query


Tag : asp.net , By : Bo.
Date : March 29 2020, 07:55 AM
wish of those help I found the answer. The MeetingSearchResult object I was returning didn't have a property representing the column being sorted on, so that column wasn't included in the database query. Obvious I guess but had me baffled for ages. Also explains why sorting on other columns worked OK.
+1 to @saamorim for acting as a fresh pair of eyes and pointing me at context.Database.Log which I wasn't aware of.

Entity Framework - Refresh without losing changes


Tag : chash , By : agjimenez
Date : March 29 2020, 07:55 AM
To fix this issue This basically turned out to be a non-issue.
I am using a Messenger to notify my contexts when they need to refresh.
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