>>>>>Viv,
>>>>>
>>>>>After I switched to List and Linq, the performance is 10 times slower than it was :( The procedure used to execute in ~800 ms. Now it executes in 8000 ms.
>>>>
>>>>As John says, must be something else going on. Linq should be faster then a coded iteration....
>>>
>>>Right, I bet the problem is here with the CAST (that's what I was getting yesterday night)
>>>
>>>

>>> columns = (from DataRow r in reader.GetSchemaTable().AsEnumerable()
>>>                                                  select new ColumnSchema
>>>                                                      {
>>>                                                          ColumnName = (String) r["ColumnName"],
>>>                                                          ColumnSize = (Int32) r["ColumnSize"],
>>>                                                          DbType = (SqlDbType) r["ProviderType"],
>>>                                                          DataType = reader.GetFieldType((int)r["ColumnOrdinal"]),
>>>                                                          Precision = (Int16) r["NumericPrecision"],
>>>                                                          Scale = (Int16) r["NumericScale"],
>>>                                                          IsIdentity = (Boolean) r["IsIdentity"]
>>>                                                      }).ToList();

>>>
>>>I am going to debug it in a few minutes and see what needs to be adjusted.
>>
>>Why are you using reader.GetFieldType((int)r["ColumnOrdinal"]) rather than (Type) r["DataType"] ?
>
>Did you see yesterday's post from Bill F message #1579381? There is no DataType property in TableSchema in .NET 4.5 according to documentation. I'm using .NET 4.0 right now, so I haven't verified.

Just checked - works in 4.5 (I'd be very surprised if it didn't)