I just encountered very curious case in Sqlite.
I have very simple data base with only one table and one index:
"CREATE TABLE IF NOT EXISTS notes(id INTEGER PRIMARY KEY, note TEXT)";
My updates to the simple text database were very slow. Extremely slow!
I changed my code and achieved 1000 speed
Just first thought came to my mind: are you sure that 2 versions of
code mentioned do the same thing? In particular I'm asserting that
second version (under #if 1) doesn't do any actual updating and
doesn't change your database because you have wrong parameter indexes.
And one more question: why do
>- Original Message
>From: Pavel Ivanov
>To: General Discussion of SQLite Database
>Sent: Wed, February 3, 2010 11:37:17 AM
>Just first thought came to my mind: are you sure that 2 versions of
>code mentioned do the same thing? In particular I'm asserting that
>second version (under #if
On Wed, Feb 03, 2010 at 08:51:46AM -0800, a1rex scratched on the wall:
> >- Original Message
> >From: Pavel Ivanov
> >To: General Discussion of SQLite Database
> >Sent: Wed, February 3, 2010 11:37:17 AM
>
> >Just first thought came to my mind: are you sure that 2 versions of
> >code men
a1rex wrote:
> Retraction. Mea Culpa. Back to square one…
> The modified code did not write anything to the drive! But there was
> no error message from the SQLITE.
Why should there be? You have a legal statement - essentially
update notes set note=1 where id='note text';
The condition is not
If you want SQLite to support all ACID properties you cannot change
anything to speed up updates. You can only change disks to something
with higher rotation speeds or some non-rotational ones (although I'm
not sure that they will be faster).
Another thing to try is change your application structu
As a test, have you tried wrapping your updates in a transaction? That
would isolate if the slow down is the actual writing of the data to
disk.
Where is the file sitting: A local drive, or something across a network
connection?
David
On Wed, 2010-02-03 at 08:51 -0800, a1rex wrote:
> >-
Thank you kindly for all your suggestions!
>If you want SQLite to support all ACID properties you cannot change
>anything to speed up updates.
Making sure that I do not loose a character was my primary objective.
> If you are doing bulk updates, and are in a position to re-run the
> data i
>I will try to do something to that extent using timer and character
>counter.
>I hoped that I could update the text stored in the database character
>by character as fast as they come from the keyboard driver.
>Unfortunately updates noticeably slow down the display of typed
>characters.
You
> Capacity: 120.9 GB
> Speed: 7200 rpm
> Average Read Time:8.5 ms
> ...
> From this data nothing justifies the 120ms update of the record!
Look at 7200 rpm and here http://www.sqlite.org/faq.html#q19.
Pavel
On Wed, Feb 3, 2010 at 1:18 PM, a1rex wrote:
>
> Thank you kindly for all your sugges
On Wed, Feb 03, 2010 at 10:18:01AM -0800, a1rex scratched on the wall:
> ?? I/O data transfer rate - up to 100 Mbps
> ?? Sustained data transfer rate - Up to 58 Mbps
> ?? Average seek time - 8.5ms
> ?? Average latency - 4.16ms
>
> From this data nothing justifies the 120ms update of the r
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