Question

I’m trying to retrieve a row using a where clause against a DateTime.

Note: Query is an IQueryable from ISession.Query extension.

var results = Query
   .Where(row => row.TimeStampUtc == timeStampUtc);

This returns no results.

var results = Query.ToList()
    .Where(row => row.TimeStampUtc == timeStampUtc);

This returns results. (By using ToList() im avoiding the NHibernate query provider).

What trick am I missing?

Update:

SQL profiler tells me that its querying for

where row.TimeStampUtc = '2011-01-28T09:28:55.00' /* @p0 */

but the actual column value is '2011-01-28 09:28:55.987' hence no matches.

Somewhere during mapping (presumably reading) I am losing the sub-second data.

Answer 1

The problem was caused by the fact the column was used as part of a CompositeId.

I could not use CustomType on the column alone, because its ignored if the column is also defined as part of a CompositeId.

The solution is the use the Type method on the KeyProperty definition.

  mapping.CompositeId()
                .KeyProperty(x => x.Name)
                .KeyProperty(x => x.TimeStampUtc, k => k.Type("DateTime2"));