Re: [sqlite] Claimed vulnerability in SQLite: Info or Intox?

2019-01-28 Thread Vladimir Barbu
Hi, This vulnerability has been addressed in SQLite 3.26.0. When could we expect new version (official) of System.Data.SQLite which uses 3.26.0? --- Vladimir     -Original Message- From: sqlite-users [mailto:sqlite-users-boun...@mailinglists.sqlite.org] On Behalf Of Keith Medcalf

Re: [sqlite] Min/Max and skip-scan optimizations

2019-01-28 Thread Gerlando Falauto
YES! Thank you! Many thanks for the ".eqp full" tip also, that really explains a lot (though I don't really understand any of it yet). Have a great day! Gerlando On Mon, Jan 28, 2019 at 6:50 AM Keith Medcalf wrote: > > Do you perhaps want this: > > select source1, >source2, >(

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread Richard Hipp
On 1/28/19, mzz...@libero.it wrote: > Dear, > > I developed an application that need to create 1 table with thousand of rows > every time when a certain event occours. > > This works in a good way, but when the number of the tables become huge > (about 15000/2 tables) the first DataBase

[sqlite] SQLite slow when lots of tables

2019-01-28 Thread mzzdvd
Dear, I developed an application that need to create 1 table with thousand of rows every time when a certain event occours. This works in a good way, but when the number of the tables become huge (about 15000/2 tables) the first DataBase reading query, after Database open, is very slow

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread R Smith
On 2019/01/28 6:17 PM, mzz...@libero.it wrote: I developed an application that need to create 1 table with thousand of rows every time when a certain event occours. This works in a good way, but when the number of the tables become huge (about 15000/2 tables) the first DataBase reading

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread Simon Slavin
On 28 Jan 2019, at 4:17pm, mzz...@libero.it wrote: > when the number of the tables become huge (about 15000/2 tables) the > first DataBase reading query, after Database open, is very slow (about 4sec.) > while next reading operations are faster. > > How can I speed up? Put all the data in

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread Chris Locke
Why do you need to create a new table each time? Its easier to create a relational database. This means create one main table that might (for example) have a 'tableID' field, which points to just one other table. This means you only need two tables. Not 20,000+ Just an idea. Depends on what

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread Igor Korot
Hi, On Mon, Jan 28, 2019 at 10:17 AM wrote: > > Dear, > > I developed an application that need to create 1 table with thousand of rows > every time when a certain event occours. Are you coming from the FoxBase/ForPro world? Thank you. > > This works in a good way, but when the number of the

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread R Smith
When the same solution is offered in rapid intervals, it must be the correct one then! :) To elaborate on what Chris mentioned regarding relational database methodology and related tables, here is why and a good description of how to do that correctly:

[sqlite] -wal and -shm files left behind by libsqlite3.dylib

2019-01-28 Thread Carsten Müncheberg
When loading and using /usr/lib/libsqlite3.dylib (3.19.3) which is shipped with MacOS 10.13.6 I noticed that the -wal and -shm files are not deleted when closing the last connection to a database. I tested this with the sqlite3 command line tool. It does not happen when I compile and link SQLite

Re: [sqlite] Claimed vulnerability in SQLite: Info or Intox?

2019-01-28 Thread Warren Young
On Jan 28, 2019, at 1:26 AM, Vladimir Barbu wrote: > > This vulnerability has been addressed in SQLite 3.26.0. When could we expect > new version (official) of System.Data.SQLite which uses 3.26.0? Are you both using FTS3 *and* letting your users execute arbitrary SQL? Most of the time, the

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread Chris Locke
> The table name should not be meaningful to your application; nothing in > your application should conjure up a table name. I can't get my head around this advice. Is this just for this occasion, or for every application? What if I'm writing a customer address book? Am I allowed a table

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread Warren Young
On Jan 28, 2019, at 9:17 AM, mzz...@libero.it wrote: > > I developed an application that need to create 1 table with thousand of rows > every time when a certain event occours. > > This works in a good way, but when the number of the tables become huge > (about 15000/2 tables) the first

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread Warren Young
On Jan 28, 2019, at 2:44 PM, Chris Locke wrote: > >> The table name should not be meaningful to your application; nothing in >> your application should conjure up a table name. > > I can't get my head around this advice. Is this just for this occasion, or > for every application? What if I'm

Re: [sqlite] -wal and -shm files left behind by libsqlite3.dylib

2019-01-28 Thread Richard Hipp
On 1/28/19, Carsten Müncheberg wrote: > When loading and using /usr/lib/libsqlite3.dylib (3.19.3) which is shipped > with MacOS 10.13.6 I noticed that the -wal and -shm files are not deleted > when closing the last connection to a database. I tested this with the > sqlite3 command line tool. It

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread Simon Slavin
On 28 Jan 2019, at 9:44pm, Chris Locke wrote: >> The table name should not be meaningful to your application; nothing in your >> application should conjure up a table name. > > I can't get my head around this advice. Is this just for this occasion, or > for every application? What if I'm

Re: [sqlite] SQLite slow when lots of tables

2019-01-28 Thread James K. Lowden
On Mon, 28 Jan 2019 16:28:41 + Simon Slavin wrote: > SQL is not designed to have a variable number of tables in a > database. All the optimization is done assuming that you will have a > low number of tables, and rarely create or drop tables. This. The table name should not be meaningful

[sqlite] SEE Temp Files

2019-01-28 Thread Jim Borden
Having moved from SQLCipher to SEE some time ago, the old advice that SQLCipher gave has stuck with me (from https://www.zetetic.net/sqlcipher/design/ in the Database Encryption and Temporary Files section): “Provided that you taken the important step of disabling file base temporary stores

Re: [sqlite] SEE Temp Files

2019-01-28 Thread Richard Hipp
On 1/28/19, Jim Borden wrote: > I see. That complicates things a bit. What happens to SQLite temp files > when they are "done being used" (if such a concept exists). Are they > deleted or simply left there for the OS to clean up? SQLite calls unlink() immediately after open(). So the OS

Re: [sqlite] SEE Temp Files

2019-01-28 Thread Richard Hipp
Intermediate results may be written into a temp file, if they overflow memory. This could result in an information leak, yes. On the other hand, if you set SQLITE_TEMP_STORE=2 so that intermediate results are held in memory, then intermediate results may be written to swap space when the device

Re: [sqlite] SEE Temp Files

2019-01-28 Thread Jim Borden
I see. That complicates things a bit. What happens to SQLite temp files when they are "done being used" (if such a concept exists). Are they deleted or simply left there for the OS to clean up? Jim Borden On 2019/01/29 8:35, "sqlite-users on behalf of Richard Hipp" wrote:

[sqlite] Inverted index without FTS

2019-01-28 Thread Jens Alfke
Part of what the FTS extension does is maintaining an inverted index. Is it possible to use this inverted-index functionality without the rest of FTS? I imagine it would involve modifications to the FTS5 code, but could those be minor or would it require extensive hacking? Or alternatively, is

Re: [sqlite] -wal and -shm files left behind by libsqlite3.dylib

2019-01-28 Thread Scott Perry
This is expected behaviour. As Richard guessed, the system libsqlite3.dylib is built with SQLITE_ENABLE_PERSIST_WAL. For Darwin systems, the compromise of keeping the extra 4MiB (max) file around is generally worth the reduced I/O overhead that results from creating, resizing, and unlinking

Re: [sqlite] -wal and -shm files left behind by libsqlite3.dylib

2019-01-28 Thread Carsten Müncheberg
Am Mo., 28. Jan. 2019 um 20:01 Uhr schrieb Richard Hipp : > On 1/28/19, Carsten Müncheberg wrote: > > When loading and using /usr/lib/libsqlite3.dylib (3.19.3) which is > shipped > > with MacOS 10.13.6 I noticed that the -wal and -shm files are not deleted > > when closing the last connection to

[sqlite] Custom aggregate functions in Tcl

2019-01-28 Thread Andy Goth
I wish to define custom aggregate functions in Tcl, but this capability is currently not exposed through the Tcl interface. Thus I am thinking about how best to add it. Here's a first crack at a design proposal: Extend the [db function] command to accept an -aggregate switch that makes the new

[sqlite] Minor concern with alter table .. rename to ..

2019-01-28 Thread Olivier Mascia
Dear, I have minor a concern with alter table .. rename to ... Please follow this sample (3.26.0): sqlite> create table T(A integer); sqlite> .schema T CREATE TABLE T(A integer); sqlite> alter table T rename to X; sqlite> .schema X CREATE TABLE IF NOT EXISTS "X"(A integer); A. Why does X needs

Re: [sqlite] Support for System.Data.SQLite: Different API type for int/integer columns

2019-01-28 Thread Barry
I use Convert.ToInt32 (or whatever else is appropriate) instead of direct casts when reading from System.Data.SQLite... I use a very similar schema in an SQLServer and SQLite database, and Convert seems to handle many of the differences without requiring different code for each database engine.