Upgrade to Lion

Peter Haworth pete at lcsql.com
Thu May 31 18:08:23 EDT 2012


Hi Kay,
You raise some interesting theories.

For your gps-based system, I would have recommended that you take a look at
the sqlite rtree extension which is specifically geared to range-based
queries such as gps coordinates.  Unfortunately, the version of the sqlite
library that is currently embedded in Livecode doesn't support it but just
in case it becomes of interest in the future, you can find more info at
http://www.sqlite.org/rtree.html.  One of the many QCC reports from me
regarding sqlite is a request to provide an updated library but so far, no
response.

I've heard nothing but good things regarding Valentina as far as it's speed
of retrieval.  Unfortunately, I haven't had a chance to try it out yet, but
it's on my radar for the near future.

I was hoping you had found something to explain some of my Lion issues in
your comment about excluding the Time Machine backup disk from Spotlight
but when I look at my spotlight preferences, the backup drive is listed
there as being excluded, just as it was before upgrading to Lion.  Maybe
I'm misunderstanding what you said?

Pete
lcSQL Software <http://www.lcsql.com>



On Thu, May 31, 2012 at 2:17 AM, Kay C Lan <lan.kc.macmail at gmail.com> wrote:

> Peter,
>
> Please accept my apology for the slow reply but my access to this List can
> be sporadic.
>
> I'm sure you are more wise than I am in this regard as I've gleaned many
> SQL tidbits from your posts to this List.
>
> As for SQLite being ubiquitous on moblie devices, in my own opinion it's
> due more to it's price, like mySQL and gmail. If people had to pay $5 a
> month for the privilege I think suddenly the numbers would shift. Just
> because a billion people do, doesn't mean it's the best.
>
> Why is my phone noticeably slower, after start-up, no apps running, just
> basic navigation, even though it's just under 30% full, compared to when it
> was new? Is it because the dbs that keep track of all that stuff have grown
> considerably in size? Is it because the data output is much larger, instead
> of a page of 8 icons, it's now always pages of 16 icons?
>
> I have three particular 3rd party desktop apps that use SQLite; two store
> gps data, the third is a home inventory program.
>
> I love the home inventory program, it has a lot of cool features, like
> looking up products based on a bar code it sees via my isight camera. But
> as I add more and more photos, and the data gets larger and much larger,
> the program gets slower and slower. Bad code on behalf of the vendor that
> could be tweaked better, probably, but that would be evidence that you can
> get it wrong.
>
> Earlier this year I took 130 million data points from the gps database and
> fed them into my own SQLite and Valentina dbs. Basically I needed to find
> the gradient that represented optimum rate of climb. To do this I needed to
> locate all hills, sift out those that where downhill rather than uphill,
> remove any instance where drafting was a factor and then seasonally, time
> of day, compare to extract trends.
>
> The sql statements were not that complex, just a LOT of toing and froing
> between LC and the db. I soon abandoned SQLite as it was clear that
> Valentina was getting the answers quicker. SQLite still did an excellent
> job, it was just slower.
>
> Maybe it has more to do with the speed LC talks to each db. I used the LC
> db commands for SQLite whilst I've migrated across to using API calls for
> Valentina.
>
> You are undoubtedly correct that the Mac has used SQLite for years, and I
> guess the reason for the major upgrades to iTunes and iPhoto that require
> complete rebuilds of the db and no turning back, is because these dbs are
> continually being tweaked for performance - and they do a brilliant job.
> But it must be easier to update a db when you know exactly what data you
> are dealing with is, ie as cameras have grown from 5 megapixel to 20
> megapixel, and added gps position.
>
> But what about Spotlight where the data is presented in a unknown vast
> assortment? I can do a search on 'Borrower' and 'Latitude', because
> Spotlight can look into the home inventory and gps dbs. How could Apple
> possibly have known that such fields would be added and whether the field
> would hold a constant 2 chars or 0-2K chars or a blob of binary. As far as
> I know there is limit of 62 dbs which SQLite can attach to. How close is
> Spotlight to reaching that limit, I've no clue, but Versions has just added
> one more, and as anything approaches it limit, it slows.
>
> As for Industrial Strength I'd go with 10s of millions of records and
> Terabytes of data.
>
> My desktop Mac has 9TB of internal storage running at 60% and 8TB of
> external, mainly for backups. When Spotlight chokes (even pre Lion) I
> assume they didn't envisage it would be indexing 10s of millions of Lats,
> Longs & Altitudes hidden amongst Terabytes of data.
>
> In Lion the number of dbs has increased, the data Versions deals with is
> unknown, and and what with Auto Save and Versions, Spotlight is being
> triggered to index more often. Also the definition of the Mac users seems
> to have narrowed. I think many on this List use their Macs in vastly
> different ways than the average Mac user, maybe outside the optimum way the
> various dbs have been set up to track their every move and keep them within
> the walls. It wont be the No1 factor, but I feel it is a factor.
>
> But I'm often wrong. And I see why, once all these dbs are set-up, indexed
> and connected, there should be very neglible processing required to just
> keep updating the data. Yet why, on my wife's Lion machine (I don't run
> Lion yet) which has been set up since Christmas, have I been prevented, on
> a couple of occassions now, from using Spotlight because it's in the middle
> of Indexing*** - is it some kind of catch22, the system will be fully
> responsive once Indexing stops, but it keeps indexing because Version keeps
> changing things.
>
> *** Oh and I've just discovered another change to Lion to add to the
> catch-22. Previous to Lion, setting up a TimeMachine HD would automatically
> exclude it from Spotlight Indexing. In Lion that doesn't happen, and if you
> try to exculde the HD you are met with a dialog that tells you that
> Spotlight will CONTINUE to Index your backups, but anything else on the
> disk (which Apple recommends you don't do) will not be. So now Spotlight
> Indexes when Lion Auto Saves, Versions Saves, TimeMachine back-ups + any
> User induced Saves. Previously it was only during user induced saves.
>
> I'm assured that Linux is a zippier resource dieted OS. Does it have a
> variety of SQLite dbs, all interconnected, and keeping track of your every
> move? Granted, OS X's iCandy is more at fault here.
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