Yes, but this would still be slow, because lastValue is lets say page 50 in
the telephone directory, but I need to go to page 800.
So this query would still return all pages from 50 to 800, which I dont need.
Am 24.05.2017 um 10:45 schrieb Andy Ling:
Then when you detect a jump you'll need to use a new search to "jump" to the
page you want. Something like
SELECT .... WHERE sortedColumn > lastValue ORDER BY sortedColumn
And make sure you have indexes on all the columns that you can sort by.
Andy Ling
-----Original Message-----
From: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] On
Behalf Of Thomas Flemming
Sent: Wed 24 May 2017 10:37
To: sqlite-users@mailinglists.sqlite.org
Subject: Re: [sqlite] SQLite3.Step fast forward / skipping rows
Almost, but when you compare to a telephone directory, then the use case of
fast scrolling down in a listbox would be going directly to page 800 and not
going to "Smithson".
And yes, there is a unique key, but this doesn't help, because the list can
also be sorted to various columns.
Am 24.05.2017 um 10:27 schrieb Keith Medcalf:
You need to write your application like a telephone directory. To get to
the page with the "Smithson" entry on it, you do not read all the entries
starting from the begining until you get there -- you turn directly to the
page you want by doing a search.
Surely you have a unique key for the list?
-- ˙uʍop-ǝpısdn sı ɹoʇıuoɯ ɹnoʎ 'sıɥʇ pɐǝɹ uɐɔ noʎ ɟı
-----Original Message----- From: sqlite-users
[mailto:sqlite-users-boun...@mailinglists.sqlite.org] On Behalf Of Thomas
Flemming Sent: Wednesday, 24 May, 2017 02:09
To:sqlite-users@mailinglists.sqlite.org Subject: [sqlite] SQLite3.Step
fast forward / skipping rows
Hi SQLite Users,
I have a SELECT query, which returns some 100000 records and is
displayed in a scrollable ListView.
When the user scrolls down the list, each new row is loaded with
SQLite3.Step().
The problem is, when the user scrolls fast with the scroll-slider, lots
of rows are skipped, but SQLite still needs to load them all with
SQLite3.Step until it reaches the row which is actually needed. This is
very slow.
Is there a way to skip all these unnecessary rows? For example going
directly from row 1000 to row 100000 ? I tried SELECT ... OFFSET 100000
but this is also very slow the more down we go.
Thanks Tom
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