Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Roger Binns
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 15/09/12 18:23, Simon Slavin wrote: > PRAGMA lint_mode=ON I'm sure there is some ideal to preserve the "Lite" part of the name and a lint mode would be quite intrusive. I can imagine a separate compilation mode (eg another #define), or some

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Simon Slavin
On 16 Sep 2012, at 2:16am, Roger Binns wrote: > It would be *really* helpful if there was some way to put SQLite into a > mode by which developers using it can test and improve their own apps. If > their app worked in that lint/test mode they would know that the chances

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Roger Binns
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 15/09/12 11:57, Richard Hipp wrote: > ... and that this change merely exposes their brokenness. I won't > dispute that. Nevertheless, with this changes, those applications will > stop working. There is the lint mode request:

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Simon Slavin
On 15 Sep 2012, at 7:57pm, Richard Hipp wrote: > So my thinking now is that this optimization should not be merged to trunk > unless it is first disabled by default and only enabled by a compile-time > or start-time option. How about for SQLite4 ? Simon.

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Elefterios Stamatogiannakis
On 15/09/12 21:57, Richard Hipp wrote: So my thinking now is that this optimization should not be merged to trunk unless it is first disabled by default and only enabled by a compile-time or start-time option. IMHO, a pragma that enables/disables it persistently on a DB would be ideal. Many

Re: [sqlite] 1.0.76 Version

2012-09-15 Thread Kevin Benson
On Sat, Sep 15, 2012 at 2:32 PM, wrote: > Hi, > > Please i need sqlite-netFx40-setup-bundle-**x64-2010-1.0.76.0.exe. Does > anyone have it in his archive? > > Regards, > > Tope. The SQLite downloads wiki is conveniently set up with file URLs that allow for

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Richard Hipp
A more complete implementation of fullscan-by-covering-index can be seen here: http://www.sqlite.org/src/info/cfaa7bc128 Many of the changes were the addition of an "ORDER BY rowid" clause to test queries in the test suite. For the previous 12 years, SQLite has always returned content in

[sqlite] 1.0.76 Version

2012-09-15 Thread db . subscriptions
Hi, Please i need sqlite-netFx40-setup-bundle-x64-2010-1.0.76.0.exe. Does anyone have it in his archive? Regards, Tope. ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Elefterios Stamatogiannakis
I have a question. Will the covering index scan optimization also cover the automatically created indexes? So lets say that for a certain part of a query, the optimizer decides to create an automatic index. Will the same index be chosen for doing a scan (instead of a full table scan) for

Re: [sqlite] System.Data>SQLite locking problem

2012-09-15 Thread Serge Fournier
I can confirm that the problem only exist when the database is encrypted. On Sat, Sep 15, 2012 at 11:00 AM, Serge Fournier wrote: > I work with an encrypted database and it look like it could be part of the > problem. > > > On Wed, Sep 12, 2012 at 3:05 PM, Serge Fournier

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Elefterios Stamatogiannakis
On 15/09/12 17:03, Simon Slavin wrote: On 15 Sep 2012, at 12:08pm, Elefterios Stamatogiannakis wrote: What i would really like to have in SQLite concerning OLAP, would be bigger pages, You can set pagesize for a new database using a PRAGMA:

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Yuriy Kaminskiy
Simon Slavin wrote: > On 15 Sep 2012, at 12:08pm, Elefterios Stamatogiannakis > wrote: > >> What i would really like to have in SQLite concerning OLAP, would be bigger >> pages, > > You can set pagesize for a new database using a PRAGMA: > >

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Richard Hipp
On Fri, Sep 14, 2012 at 5:24 PM, Roger Binns wrote: > -BEGIN PGP SIGNED MESSAGE- > Hash: SHA1 > > >> Is there a chance that the change will go into SQLite mainline? > > > > Not without a copyright release. > > And it may require more especially if you are an

Re: [sqlite] Question about the sqlite3_column_bytes

2012-09-15 Thread Clemens Ladisch
kjell.gunnars...@sungard.com wrote: > sqlite3_column_bytes returns an "int" Yes. > that can contain values in the interval -32768 to +32767. It is assumed that any platform SQLite runs on has as least 32 bits. (And if you'd want to run SQLite on MS-DOS, the type of sqlite3_column_bytes's

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Simon Slavin
On 15 Sep 2012, at 12:08pm, Elefterios Stamatogiannakis wrote: > What i would really like to have in SQLite concerning OLAP, would be bigger > pages, You can set pagesize for a new database using a PRAGMA: The maximum

Re: [sqlite] Problem in sqlite3VXPrintf due to floating point optimization

2012-09-15 Thread Richard Hipp
On Fri, Sep 14, 2012 at 4:49 PM, van der Merwe, Ben wrote: > Hi, > > If we compile sqlite3.c (version 3.7.14) using Microsoft Visual C++ 2010 > with maximum optimization, /Ox, then we experience this problem: > > The code in sqlite3VXPrintf is sensitive to numerical

[sqlite] Problem in sqlite3VXPrintf due to floating point optimization

2012-09-15 Thread van der Merwe, Ben
Hi, If we compile sqlite3.c (version 3.7.14) using Microsoft Visual C++ 2010 with maximum optimization, /Ox, then we experience this problem: The code in sqlite3VXPrintf is sensitive to numerical optimization. With optimizations turned on, a number like: 99.943 *sometimes* is

[sqlite] Possible bug: Pager->zJournal not double-null terminated

2012-09-15 Thread Masashi Ito
Hello folks, I've noticed that the zJournal string in the Pager struct isn't double-null terminated, but goes through the same open file routines which seem to expect the double null. This has caused a crash condition in conjunction with the async module. The crash happens at line 115866 of

[sqlite] Question about the sqlite3_column_bytes

2012-09-15 Thread kjell.gunnarsson
Hi, sqlite3_column_bytes should be used to get info about the length of the Blob-data when extracting data from a table that contains a BLOB column. sqlite3_column_bytes returns an "int" that can contain values in the interval -32768 to +32767. But what happens if it is more bytes in the BLOB

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Elefterios Stamatogiannakis
On 14/09/12 22:56, Clemens Ladisch wrote: But do you have any numbers (which would help deciding whether to accept this patch)? I've run two queries on two different DBs: - DB1: Size 414M, Count of recs 2999671, the table has 17 Cols - DB2: Size 1.4G, Count of recs 1975986, the table has

Re: [sqlite] Covering index scan optimization

2012-09-15 Thread Elefterios Stamatogiannakis
On 14/09/12 22:56, Clemens Ladisch wrote: Elefterios Stamatogiannakis wrote: On 13/09/12 23:02, Clemens Ladisch wrote: For my main workload (OLAP) this can make an enormous difference! OLAP isn't quite the typical SQLite use case. But do you have any numbers (which would help deciding