Re: Informix vs. Sybase vs. Oracle vs. (gasp) MS SQL Server

In article <3482318D.C4112DA5_at_voicenet.com>, "Scott C. Gray" <ickyspam_gray_at_voicenet.com> writes
>David Williams wrote:
>>
>> In article <3481D92B.75AA9F0D_at_voicenet.com>, "Scott C. Gray"
>> <ickyspam_gray_at_voicenet.com> writes
>> >> page level locks give HIGHER PERFORMANCE yes BItUT the reduce
>> >> concurrency and hence LOWER RELIABILITY.
>> >
>> >Be careful with your wording...locking granularity has nothing at
>> >all to do with reliability (indeed, table locking vs. column locking
>> >has the same reliability when properly implemented). It is all
>> >simply a matter of concurrency and efficiency.
>>
>> Most applications produce an error when a lock error occurs.
>>
>
>I assume that you are referring to deadlocks. While it is true that
>deadlocks may be reduced in a row vs. page locking environment, they
>can still occur (don't forget we are only talking about locking...
>not versioning--which can also be done in a page locked environment).
>
>It is foolish for any application developer to fail to check for such
>conditions (although, in my experience, almost everyone does).
>Thus, for a properly coded application, page locking does not
>reduce application reliability one bit...it just increases the
>likely hood that the proper error detection/recovery code will
>be executed (although, in a properly developed environment, it
>is possible to eliminate deadlocks anyway).
>
  Correct, the user will receive an error message saying this item cannot be updated an hence this "the application failed with an error, it is not as reliable as other applications".

>> 1. Queries fails
>> 2. Database modifications produce an error and the transaction is
>> rolled back (few applications retry).
>>
>> Hence APPLICATION RELIABLITIY is reduce.
>
>Once again...be careful about your wording. It seems that you
>are producing a false analogy along the lines of:
>
> 1. Some conditions cause the database to generate an
> error.
> 2. Many applications don't check for these errors
>
> The database is not working properly.
>
  No, but I'm syaing the user sees more error messages and updates   which failed to complete.

-- 
David Williams