IDbConnection.Dictionary() raising exception in 6.9.0

Drammy · June 9, 2023, 4:03pm

Hi,

Is there a breaking change with IDbConnection.Dictionary<>() that we’re unaware of in 6.9.0?

Since upgrading to 6.9.0 we’re getting an Object reference not set to an instance of an object exception.

mythz · June 9, 2023, 4:26pm

Not that I know of, what’s the best way to repro?

Drammy · June 9, 2023, 5:01pm

We’ve an endpoint that has two db queries which have historically both worked. Now one works and this one fails…

var activityIdsWithDocuments = Db
                .Dictionary<long, int>(
                    Db
                        .From<DbCore.DocumentWithLookupIds>()
                        .Where(d =>
                            d.SystemId == identifiedObject.IdentifiedSystemId &&
                            d.OwnerTypeId == (int)identifiedObject.OwnerType &&
                            d.OwnerId == identifiedObject.IdentifiedObjectId)
                        .Select(d => new { d.ActivityId, d.TypeId })
                );

mythz · June 9, 2023, 5:14pm

Trying to resolve the 2nd value is throwing the NRE:

github.com

ServiceStack/ServiceStack/blob/main/ServiceStack.OrmLite/src/ServiceStack.OrmLite/OrmLiteReadCommandExtensions.cs#L852


      
              return dbCmd.Dictionary<K, V>(sql);
          }
          
          
internal static Dictionary<K, V> Dictionary<K, V>(this IDataReader reader, IOrmLiteDialectProvider dialectProvider)
          {
              var map = new Dictionary<K, V>();
          
          
    while (reader.Read())
              {
                  var key = (K)dialectProvider.FromDbValue(reader, 0, typeof(K));
                  var value = (V)dialectProvider.FromDbValue(reader, 1, typeof(V));
          
          
        map.Add(key, value);
              }
          
          
    return map;
          }
          
          
internal static List<KeyValuePair<K, V>> KeyValuePairs<K, V>(this IDbCommand dbCmd, string sql, object anonType = null)
          {
              if (anonType != null) SetParameters(dbCmd, anonType.ToObjectDictionary(), excludeDefaults: false, sql:ref sql);

Can you confirm if your query always returns non-nullable values. If it doesn’t can you change to use db.Dictionary<long,int?>

Drammy · June 9, 2023, 5:26pm

Doh, if I had a quid for every time nullable values have caused me issues since moving to .net core I’d be able to retire now.

Apologies - I should have been more thorough in testing before I submitted the forum post. It was a slightly different dataset I was testing against.

I’ve tested with int? and its working again - thanks @mythz!