I used ExecuteReturnLastId as follow sample
var id = dbContext.Insert("app").Column("name", newAppName).ExecuteReturnLastId<Int32>("id");
but the result is null. I tried to debug from the lastest main code and I found that in the
ExecuteQueryHandler.cs I have the follow piece of code
_command.Data.InnerCommand.CommandText = _command.Data.Sql.ToString();
with _command.Data.InnerCommand.CommandText == "select lastval();"
and _command.Data.Sql.ToString() == "insert into app(name) values(:name);"
as result the "select lastval();" not get appended to the sql query after the insert but the insert query simply overwrite the select last sql command text.
Attached a workaround patch, not sure if works in all cases but for me it did the trick.