Scalar vs Reader Exec Method

Hi

Is there any advantage of using scalar execution method for data adapter if
the result is going to be a single record?

Thanks

Regards

Scott
Tue May 06 18:14:57 CDT 2008

Scalar only gives you back the first field from the first record, so if you
want the whole record, don't use scalar.

Scalar is generally good for when you are calling a user function in the DB
to get back a single result.

-Scott


"John" <info@nospam.infovis.co.uk> wrote in message
news:O6C3tM8rIHA.4376@TK2MSFTNGP06.phx.gbl...
> Hi
>
> Is there any advantage of using scalar execution method for data adapter
> if the result is going to be a single record?
>
> Thanks
>
> Regards
>

William
Wed May 07 13:15:44 CDT 2008

Scott is right. But consider that the efficiency lies in the question you
ask--the query. If it returns 100 rows and you only want the first row or
the first column of the first row, ExecuteScalar won't help much. That's
because ADO.NET has to return all 100 rows before determining that there is
not another resultset to process. To make this faster, get the SELECT to
return a single value or better yet (and even faster) use the RETURN value
to capture the value (if it's an INT) or an OUTPUT parameter.

--
__________________________________________________________________________
William R. Vaughn
President and Founder Beta V Corporation
Author, Mentor, Dad, Grandpa
Microsoft MVP
(425) 556-9205 (Pacific time)
Hitchhiker's Guide to Visual Studio and SQL Server (7th Edition)
____________________________________________________________________________________________
"Scott M." <smar@nospam.nospam> wrote in message
news:%23OHxX68rIHA.2064@TK2MSFTNGP05.phx.gbl...
> Scalar only gives you back the first field from the first record, so if
> you want the whole record, don't use scalar.
>
> Scalar is generally good for when you are calling a user function in the
> DB to get back a single result.
>
> -Scott
>
>
> "John" <info@nospam.infovis.co.uk> wrote in message
> news:O6C3tM8rIHA.4376@TK2MSFTNGP06.phx.gbl...
>> Hi
>>
>> Is there any advantage of using scalar execution method for data adapter
>> if the result is going to be a single record?
>>
>> Thanks
>>
>> Regards
>>
>
>

Cor
Wed May 07 23:18:36 CDT 2008

William,

With your answer I can get the idea (as I did not know better) that you want
to say that there are situatons that the Scalar can be used instead of a
reader to get full rows.

>ExecuteScalar won't help much.
In my idea it won't help at all,

I cannot have the idea that that was the goal of your reply.

Cor

"William Vaughn [MVP]" <billvaNoSPAM@betav.com> schreef in bericht
news:9EF83503-4728-4C2F-81C6-16B786321E4C@microsoft.com...
> Scott is right. But consider that the efficiency lies in the question you
> ask--the query. If it returns 100 rows and you only want the first row or
> the first column of the first row, ExecuteScalar won't help much. That's
> because ADO.NET has to return all 100 rows before determining that there
> is not another resultset to process. To make this faster, get the SELECT
> to return a single value or better yet (and even faster) use the RETURN
> value to capture the value (if it's an INT) or an OUTPUT parameter.
>
> --
> __________________________________________________________________________
> William R. Vaughn
> President and Founder Beta V Corporation
> Author, Mentor, Dad, Grandpa
> Microsoft MVP
> (425) 556-9205 (Pacific time)
> Hitchhiker's Guide to Visual Studio and SQL Server (7th Edition)
> ____________________________________________________________________________________________
> "Scott M." <smar@nospam.nospam> wrote in message
> news:%23OHxX68rIHA.2064@TK2MSFTNGP05.phx.gbl...
>> Scalar only gives you back the first field from the first record, so if
>> you want the whole record, don't use scalar.
>>
>> Scalar is generally good for when you are calling a user function in the
>> DB to get back a single result.
>>
>> -Scott
>>
>>
>> "John" <info@nospam.infovis.co.uk> wrote in message
>> news:O6C3tM8rIHA.4376@TK2MSFTNGP06.phx.gbl...
>>> Hi
>>>
>>> Is there any advantage of using scalar execution method for data adapter
>>> if the result is going to be a single record?
>>>
>>> Thanks
>>>
>>> Regards
>>>
>>
>>
>

William
Thu May 08 18:21:43 CDT 2008

ExecuteScalar will not help performance over ExecuteReader in this case.

--
__________________________________________________________________________
William R. Vaughn
President and Founder Beta V Corporation
Author, Mentor, Dad, Grandpa
Microsoft MVP
(425) 556-9205 (Pacific time)
Hitchhiker's Guide to Visual Studio and SQL Server (7th Edition)
____________________________________________________________________________________________
"Cor Ligthert[MVP]" <notmyfirstname@planet.nl> wrote in message
news:C178481C-0FE0-47E5-8153-262AE8600C13@microsoft.com...
> William,
>
> With your answer I can get the idea (as I did not know better) that you
> want to say that there are situatons that the Scalar can be used instead
> of a reader to get full rows.
>
>>ExecuteScalar won't help much.
> In my idea it won't help at all,
>
> I cannot have the idea that that was the goal of your reply.
>
> Cor
>
> "William Vaughn [MVP]" <billvaNoSPAM@betav.com> schreef in bericht
> news:9EF83503-4728-4C2F-81C6-16B786321E4C@microsoft.com...
>> Scott is right. But consider that the efficiency lies in the question you
>> ask--the query. If it returns 100 rows and you only want the first row or
>> the first column of the first row, ExecuteScalar won't help much. That's
>> because ADO.NET has to return all 100 rows before determining that there
>> is not another resultset to process. To make this faster, get the SELECT
>> to return a single value or better yet (and even faster) use the RETURN
>> value to capture the value (if it's an INT) or an OUTPUT parameter.
>>
>> --
>> __________________________________________________________________________
>> William R. Vaughn
>> President and Founder Beta V Corporation
>> Author, Mentor, Dad, Grandpa
>> Microsoft MVP
>> (425) 556-9205 (Pacific time)
>> Hitchhiker's Guide to Visual Studio and SQL Server (7th Edition)
>> ____________________________________________________________________________________________
>> "Scott M." <smar@nospam.nospam> wrote in message
>> news:%23OHxX68rIHA.2064@TK2MSFTNGP05.phx.gbl...
>>> Scalar only gives you back the first field from the first record, so if
>>> you want the whole record, don't use scalar.
>>>
>>> Scalar is generally good for when you are calling a user function in the
>>> DB to get back a single result.
>>>
>>> -Scott
>>>
>>>
>>> "John" <info@nospam.infovis.co.uk> wrote in message
>>> news:O6C3tM8rIHA.4376@TK2MSFTNGP06.phx.gbl...
>>>> Hi
>>>>
>>>> Is there any advantage of using scalar execution method for data
>>>> adapter if the result is going to be a single record?
>>>>
>>>> Thanks
>>>>
>>>> Regards
>>>>
>>>
>>>
>>
>