I have a table with approximately 100 million registers with a index in the field the query ask. The execution plan is ok.

When I use the method Get<T> its take about 6 minutes to return data.

I make other test using de result query (show_sql=true) of Get<T> method with CreateSQLQuery and when I put the parameter inside the sql results in a immediate response (ex : SELECT fields FROM TABLE WHERE otherfield='1'). If I use SetString to fill other field values takes the same 6 minutes with Get<T> method.

Looking in NHibernate source the slow ocurrs in Loader.cs, DoQuery method rs.Read command.

One more information.

In table the field has String type and when the parameters of IDbCommand are filled, NHibernate translates to NVarchar OracleType. I force to VarChar and I have no more slows problems.

The database I'm using is Oracle 10g and these slows occurs with 1.2.1 and 2.0 version of NHibenate.

"Problem" resolved.

I found a solution this article http://community.devpinoy.org/blogs/joe ... index.aspx