How can I search for a DATE in Entity Framework

Question

I'm trying to get a date from my database and I've tried different things, but nothing seems to work.

This is my date in the database 2024-04-18 19:47:36.337, it's defined as datetime in Microsoft SQL Server; I'm using Entity Framework and C# and the variable is

public DateTime InitH { get; set; }

My query is more complex than this, but I found the problem is the date. So I try to get an optimal solution to search dates

public void obtenerFechaHarcodeada()
{
    DateTime fecha = new DateTime(2024, 4, 18, 19, 47, 36);

    var registro = _dbContext.AssignmentRecords
                             .FirstOrDefault(r=> r.InitH == fecha);
}

Any ideas?

I'm trying to save the same date and the same variable to search on the database, but it never works

Answer 1

Rather than an exact date/time value, I suggest that you search for a date/time range that covers the entire second.

DateTime fechaFrom = new DateTime(2024, 4, 18, 19, 47, 36);
DateTime fechaTo = fechaFrom.AddSeconds(1);

var registro = _dbContext.AssignmentRecords
    .FirstOrDefault(r=> r.InitH >= fechaFrom && r.InitH < fechaTo);

It is worth noting that the SQL Server DATETIME type stores times with a precision of 1/300 of a second, so the displayed value 2024-04-18 19:47:36.337 is actually closer to 2024-04-18 19:47:36.33666.... Like floating point values, it is best to avoid equality comparisons.