/// <summary>
/// Great of huge result sets, process one row at the time
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="cmd"></param>
/// <param name="processor">Result processor</param>
/// <param name="mapper"></param>
/// <param name="firstRowOnly"></param>
/// <param name="disposeConnection">True to dispose the connection</param>
public static void QueryAndProcess <T>(this DbCommand cmd, Func <T, bool> processor, Func <DbDataReader, T> mapper = null,
bool firstRowOnly = false, bool disposeConnection = false)
{
var fuCommand = cmd.CastAs <SqlFuCommand>();
var strat = fuCommand.GetErrorsStrategy();
CommandBehavior behavior = firstRowOnly ? CommandBehavior.SingleRow : CommandBehavior.Default;
SqlFuCommand.HandleTransients(cmd, () =>
{
using (var reader = cmd.ExecuteReader(behavior))
{
while (reader.Read())
{
if (!processor(cmd.GetMapper(mapper, cmd.CommandText)(reader)))
{
break;
}
}
}
}, strat, fuCommand.Provider, cmd.SqlConfig());
if (disposeConnection)
{
cmd.Connection.Dispose();
cmd.Dispose();
}
}
/// <summary>
/// Executes an async query then processes each result
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="cmd"></param>
/// <param name="cancellation"></param>
/// <param name="processor">Delegate to process a result item. Return false from delegate to end the query</param>
/// <param name="mapper"></param>
/// <param name="firstRowOnly"></param>
/// <returns></returns>
public static async Task QueryAndProcessAsync <T>(this DbCommand cmd, CancellationToken cancellation, Func <T, bool> processor, Func <DbDataReader, T> mapper = null,
bool firstRowOnly = false, bool disposeConnection = false)
{
var fuCommand = cmd.CastAs <SqlFuCommand>();
var strat = fuCommand.GetErrorsStrategy();
CommandBehavior behavior = firstRowOnly ? CommandBehavior.SingleRow : CommandBehavior.Default;
await SqlFuCommand.HandleTransientsAsync(cmd, async (c) =>
{
using (var reader = await cmd.ExecuteReaderAsync(behavior, c).ConfigureFalse())
{
while (await reader.ReadAsync(c).ConfigureFalse())
{
if (!processor(cmd.GetMapper(mapper, cmd.CommandText)(reader)))
{
break;
}
}
}
}, strat, fuCommand.Provider, cancellation, cmd.SqlConfig()).ConfigureFalse();
if (disposeConnection)
{
cmd.Connection.Dispose();
cmd.Dispose();
}
}