авторИли ODBC-драйвер, действительно, использует серверные сообщения?
ОБЯЗАТЕЛЬНО использует.
АДО тоже ОБЯЗАТЕЛЬНО использует
ИМХО client-side рекордсет никак "правильно" не заработает,
при SET NOCOUNT ON

PS
paparome, поставь BOL - любой.

пока не поставил, вот цитата (красным выделено про "попытку угадать, иногда неправильно")

SET NOCOUNT
Stops the message indicating the number of rows affected by a Transact-SQL statement from being returned as part of the results.

Syntax
SET NOCOUNT { ON | OFF }

Remarks
When SET NOCOUNT is ON, the count (indicating the number of rows affected by a Transact-SQL statement) is not returned. When SET NOCOUNT is OFF, the count is returned.

The @@ROWCOUNT function is updated even when SET NOCOUNT is ON.

SET NOCOUNT ON eliminates the sending of DONE_IN_PROC messages to the client for each statement in a stored procedure. When using the utilities provided with Microsoft® SQL Server™ to execute queries, the results prevent "nn rows affected" from being displayed at the end Transact-SQL statements such as SELECT, INSERT, UPDATE, and DELETE.

For stored procedures that contain several statements that do not return much actual data, this can provide a significant performance boost because network traffic is greatly reduced.

The setting of SET NOCOUNT is set at execute or run time and not at parse time.

Permissions
SET NOCOUNT permissions default to all users.

Examples
This example (when executed in the osql utility or SQL Query Analyzer) prevents the message (about the number of rows affected) from being displayed.

USE pubs
GO
-- Display the count message.
SELECT au_lname
FROM authors
GO
USE pubs
GO
-- SET NOCOUNT to ON and no longer display the count message.
SET NOCOUNT ON
GO
SELECT au_lname
FROM authors
GO
-- Reset SET NOCOUNT to OFF.
SET NOCOUNT OFF
GO

авторчитать я тоже умею
это хорошо.
я вот, к сожалению, не возьмусь похвастать...

авторSELECT @@ROWCOUNT честно вернет, 240? или нет
вернет (если его никто не успеет попортить, например следующая команда в батче типа IF @@ERROR)