Dapper.NET and stored proc with multiple result sets

QueryMultiple supports the ability to deal with multiple result sets. The only design restriction we added was totally disabling buffering for the grid reader. This means the whole API is streaming.

In the simplest case you can use:

var grid = connection.QueryMultiple("select 1 select 2");
grid.Read<int>().First().IsEqualTo(1);
grid.Read<int>().First().IsEqualTo(2);

In the slightly more sophisticated case you can do crazy stuff like this:

var p = new DynamicParameters();
p.Add("a", 11);
p.Add("r", dbType: DbType.Int32, direction: ParameterDirection.ReturnValue);

connection.Execute(@"create proc #spEcho
@a int
as 
begin

select @a Id, 'ping' Name, 1 Id, 'pong1' Name
select @a Id, 'ping' Name, 2 Id, 'pong2' Name
return @a
end");

var grid = connection.QueryMultiple("#spEcho", p, 
                                     commandType: CommandType.StoredProcedure);

var result1 = grid.Read<dynamic, dynamic, Tuple<dynamic, dynamic>>(
                  (a, b) => Tuple.Create((object)a, (object)b)).ToList();
var result2 = grid.Read<dynamic, dynamic, Tuple<dynamic, dynamic>>(
                  (a, b) => Tuple.Create((object)a, (object)b)).ToList();

((int)(result1[0].Item1.Id)).IsEqualTo(11);
((int)(result1[0].Item2.Id)).IsEqualTo(1);

((int)(result2[0].Item1.Id)).IsEqualTo(11);
((int)(result2[0].Item2.Id)).IsEqualTo(2);

p.Get<int>("r").IsEqualTo(11);

You’ll need to add this using statement to enable QueryMultiple .

using Dapper; /* to add extended method QueryMultiple public static GridReader QueryMultiple(this IDbConnection cnn, string sql, object param = null, IDbTransaction transaction = null, int? commandTimeout = null, CommandType? commandType = null); */

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