MySQL Performance Example Was: Seriously, WTF?
Robbie Bow
robbiebow at gmail.com
Sat May 10 16:20:49 BST 2008
On Sat, May 10, 2008 at 4:20 PM, Robbie Bow <robbiebow at gmail.com> wrote:
> On Sat, May 10, 2008 at 7:58 AM, Jonathan Stowe <jns at gellyfish.com> wrote:
>> On Fri, 2008-05-09 at 20:41 +0100, Robbie Bow wrote:
>>> On Fri, May 9, 2008 at 4:21 PM, Abigail <abigail at abigail.be> wrote:
>>> >>
>>> >> Go on then, tell me the easier, better way to hold these 100 million
>>> >> records and perform the kind of searches in question. Or even the
>>> >> transactions one should be "bothered" with in this scenario.
>>> >
>>> > Those 100 million records have to come from somewhere, did the rows
>>> > come with your version of MySQL? All MySQLs I installed just came with
>>> > empty tables.
>>> >
>>> > I agree, there are cases where you don't need a transaction if you are
>>> > searching. But I don't want to go from 0 rows to even 1 row without
>>> > transactions, let alone to 100 million.
>>> >
>>>
>>> What do we gain from transactions when the only task is to insert data
>>> e.g. we go from
>>>
>>> insert
>>>
>>> to:
>>>
>>> begin
>>> insert
>>> commit
>>
>> My understanding is that without transactions in the database engine the
>> first is still afflicted by the fact that the update of the index is not
>> atomic to the insert, your insert might succeed and the index update
>> might fail - if subsequently the query optimizer chooses to use the
>> corrupt index to perform a query then your row has disappeared.
>>
>
> I think that is mitigated if you ensure the myisam-recover server is
> set appropriately.
>
s/server/server option/
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