Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

Quoth Nico Williams , on 2013-04-04 19:15:52 -0500: > This is off-topic, I know, so maybe we should continue this off-list, > if at all, but... Switching to private mail. ---> Drake Wilson ___ sqlite-users mailing list

[sqlite] Restrictions on JOINs with FTS tables

Hi there, I'm wondering if someone could help me understand the restrictions of queries that mix regular tables with FTS tables. Let's say you've got the following two tables, which have related records: CREATE TABLE indexes(recID int, metadata1 int);  CREATE VIRTUAL TABLE texts USING

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

On Thu, Apr 4, 2013 at 4:45 PM, Drake Wilson wrote: > Quoth Nico Williams , on 2013-04-04 16:08:24 -0500: >> This is very sad. But really, the OS should cause kvserv to hang >> waiting for I/O from the device to complete (and you should get some >>

[sqlite] FTS Find Tokens at Record Start

Hi there, I couldn't find this from the documentation: using FTS, how do you match records that contain certain tokens beginning at the start of the record (or any token position for that matter). For example, I want to match records that start with "Four score and seven years ago" but not

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

Quoth Nico Williams , on 2013-04-04 16:08:24 -0500: > This is very sad. But really, the OS should cause kvserv to hang > waiting for I/O from the device to complete (and you should get some > indication, in dmesg, on the console, in a dialog -something- that > there's a

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

On Thu, Apr 4, 2013 at 11:44 AM, Drake Wilson wrote: > Repeating these steps, but compiling the application with the > sqlite3.c from the 201304040051 snapshot amalgamation that uses > unprotected mmap, causes the entire kvserv process to die with SIGBUS > as soon as a query

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

"Richard Hipp" wrote... By making use of memory-mapped I/O, the current trunk of SQLite (which will eventually become version 3.7.17 after much more refinement and testing) can be as much as twice as fast, on some platforms and under some workloads. We would like to encourage people to try

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

Quoth Drake Wilson , on 2013-04-04 10:20:44 -0500: > So it is perfectly okay to use unprotected mmap accesses if an I/O > error on the file will already make the entire process uncontinuable. > The question is whether this applies to arbitrary SQLite databases > that an

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

On Thu, Apr 4, 2013 at 8:19 AM, Howard Chu wrote: > This is why OpenLDAP LMDB uses a read-only mmap by default. User bugs get an > immediate SEGV, and usually the bug becomes obvious and easy to fix. There are many reasons to want to use read-only mmap()s (with MAP_SHARED though)

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

Quoth Richard Hipp , on 2013-04-04 10:51:22 -0400: > Is this really a problem? Your executable and all of your shared libraries > are also mmapped into your address space. If accessing mmapped memory were > causing bus errors, then we'd be seeing bus errors all over the place.

Re: [sqlite] Implementing "Save As..." functionality for Application File Format usecase

Gaspard Bucher founder, coder teti sàrl (http://teti.ch) On Wednesday, 3 April 2013 at 23:11, Tiago Rodrigues wrote: > Hello all, > > I'm writing a small simulation app and for it I would like to use SQLite3 > as an application file format, as suggested by the "Appropriate

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

On Thu, Apr 4, 2013 at 9:22 AM, Teg wrote: > Hello Richard, > > How much do you map at a time? The default on windows is currently 256MiB. You can adjust this number up or down using a pragma. Or you can change it at compile-time or start-time. > I've virtually abandoned

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

On Thu, Apr 4, 2013 at 9:02 AM, Ryan Johnson wrote: > On 04/04/2013 8:02 AM, Richard Hipp wrote: > >> By making use of memory-mapped I/O, the current trunk of SQLite (which >> will >> eventually become version 3.7.17 after much more refinement and testing) >> can be

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

On Thu, Apr 4, 2013 at 8:43 AM, Drake Wilson wrote: > Quoth Richard Hipp , on 2013-04-04 08:02:34 -0400: > > By making use of memory-mapped I/O, the current trunk of SQLite (which > will > > eventually become version 3.7.17 after much more refinement and

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

Dan Kennedy wrote: On 04/04/2013 08:44 PM, Howard Chu wrote: Richard Hipp wrote: The memory-mapped I/O is only enabled for windows, linux, mac OS-X, and solaris. We have found that it does not work on OpenBSD, for reasons we have not yet been able to uncove; but as a precaution, memory mapped

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

On 04/04/2013 08:44 PM, Howard Chu wrote: Richard Hipp wrote: The memory-mapped I/O is only enabled for windows, linux, mac OS-X, and solaris. We have found that it does not work on OpenBSD, for reasons we have not yet been able to uncove; but as a precaution, memory mapped I/O is disabled by

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

Richard Hipp wrote: The memory-mapped I/O is only enabled for windows, linux, mac OS-X, and solaris. We have found that it does not work on OpenBSD, for reasons we have not yet been able to uncove; but as a precaution, memory mapped I/O is disabled by default on all of the *BSDs until we

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

Hello Richard, How much do you map at a time? I've virtually abandoned memory mapped files in Win32 because of address space limitations. There's a 2 GB address space limit in Win32 (most of the time) so, if the combination of allocated RAM and memory mapped file size bump into the limit, the

Re: [sqlite] How to achieve fastest possible write performance for a strange and limited case

Thanks for everyone's help and thoughts on this issue. My findings on Windows 7 Pro 64 using a PCI based SSD is that for my smallish image the BLOBs were faster than individual files. Basically, in line with a table that someone posted earlier in this thread. After many experiments, with many

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

Ryan Johnson wrote: 3. It seems like this would increase the "attack surface" for stray pointers in the host program. Granted, writes to stray pointers are not sqlite's fault, but they're an unfortunately common problem... and mmap makes user bugs more likely to directly corrupt the database on

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

On 04/04/2013 8:02 AM, Richard Hipp wrote: By making use of memory-mapped I/O, the current trunk of SQLite (which will eventually become version 3.7.17 after much more refinement and testing) can be as much as twice as fast, on some platforms and under some workloads. Nice! Some quick

Re: [sqlite] SQLite 3.7.17 preview - 2x faster?

Quoth Richard Hipp , on 2013-04-04 08:02:34 -0400: > By making use of memory-mapped I/O, the current trunk of SQLite (which will > eventually become version 3.7.17 after much more refinement and testing) > can be as much as twice as fast, on some platforms and under some >

Re: [sqlite] Implementing "Save As..." functionality for Application File Format usecase

On Wed, Apr 3, 2013 at 5:11 PM, Tiago Rodrigues wrote: > Hello all, > > I'm writing a small simulation app and for it I would like to use SQLite3 > as an application file format, as suggested by the "Appropriate uses for > SQLite" page in sqlite.org. More specifically, the

Re: [sqlite] How to install sqlite 3.7.11

On 4 Apr 2013, at 8:16am, Pratik Patodi wrote: > The object file is ready for use but, I can figure out where the database > is actually getting stored. > I mean that when, I run the sqlite3 object file and then the command: > *.database* I get these database: > >

[sqlite] Report a sqlite record deletion problem

A free block list is not built well when a record in a leaf page is deleted. The list doesn't hold all free blocks sometimes. The bad list of deleted record cells makes recovery not that easy. For example:(showed in pictures) 1.1.png and 1.2.png: is after the the deletion of the record with

Re: [sqlite] How to install sqlite 3.7.11

@Ryan : Thanks for you reply i tried your way got some linkage error but I figured it out the final command which work was: *gcc -O2 -lpthread -ldl sqlite3.c shell.c -o sqlite3 * The object file is ready for use but, I can figure out where the database is actually getting stored. I mean that

Re: [sqlite] Implementing "Save As..." functionality for Application File Format usecase

Am 03.04.2013 23:11, schrieb Tiago Rodrigues: I'm writing a small simulation app and for it I would like to use SQLite3 as an application file format, ... > ... For that, the simplest idea would be to use the online backup family of functions, calling sqlite3_backup_init() and

[sqlite] SQLite 3.7.17 preview - 2x faster?

By making use of memory-mapped I/O, the current trunk of SQLite (which will eventually become version 3.7.17 after much more refinement and testing) can be as much as twice as fast, on some platforms and under some workloads. We would like to encourage people to try out the new code and report

[sqlite] Need JDBC driver for SQLite

Hello All, I was looking for an authoritative source from where I can get the driver (jar) for SQLite. SQLite web site do not have any mention for Java support. Can anyone help in getting the JDBC driver for SQLite (from trusted source only)? Thanks