DateTimeOffset comparision in ORMLite query

ServiceStack.OrmLite
1

Hello,

I am converting a small ASP.Net WebAPI application into a ServiceStack app.
At the time of dealing with a query that uses DateTimeOffset I am getting error:
System.NullReferenceException:
“Object reference not set to an instance of an object”

Thrown by:

public NCNNumber LastEntryAt(DateTimeOffset date)
{
    var q = Db.From<NCNNumber>()
            .Where(e => e.CreatedAt.Year == date.Year)
            .Where(e => e.CreatedAt.Month == date.Month)
            .Where(e => e.CreatedAt.Day == date.Day)
            .OrderByDescending(e => e.Sequence);

    return Db.Single(q);
}

So far I had to use the following code which works, but I would like to understand why the code above did not work.
This is working: (I had to remove dollar sign of interpolated strings, don’t know how to escape them in here):

public NCNNumber LastEntryAt(DateTimeOffset date)
{
    var q = Db.From<NCNNumber>();
    q.Where("(DATEPART(year, {q.Column<NCNNumber>(n => n.CreatedAt)})) = {date.Year}");
    q.Where("(DATEPART(month, {q.Column<NCNNumber>(n => n.CreatedAt)})) = {date.Month}");
    q.Where("(DATEPART(day, {q.Column<NCNNumber>(n => n.CreatedAt)})) = {date.Day}");
    q.OrderByDescending(n => n.Sequence);

    return Db.Single(q);
}
2

In general OrmLite doesn’t support c# property access on RDBMS Server columns.

It only supports some very specific string methods documented on the project page, but in general if you don’t see C# method or property access documented anywhere it’s not supported.

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