Re: [sqlite] SQLite server/file-locking scenario

On 19 Nov 2013, at 6:00am, Joshua Grauman wrote: > sqlite3_open_v2("sqlite3.database.filename"); > sqlite3_exec("BEGIN IMMEDIATE"); > file.open("sqlite3.database.filename"); > file.readAll(); > file.close(); > sqlite3_exec("ROLLBACK"); > sqlite3_close(); > > So does this

Re: [sqlite] Why must WITHOUT ROWID tables have PRIMARY KEYs?

On 2013/11/19 08:37, Nico Williams wrote: More generally however, it's clear that a unique constraint is not necessary to make rowid-less tables work (see the MySQL example), SQL doesn't require unique constraints, and it's not clear that just because you (or I) lack imagination that unique

[sqlite] Fwd: Creating a Local DB for a WPF application

Hii, I have .net 4.0 WPF application.My Active Solution platform is "Any CPU" and I'm running on a 64 bit Windows 7 system.I have used Sqlite.It works fine on my system.But when i am installing my application to some other machin,i am getting an error "An attempt was made to load a program with an

[sqlite] SQlite3 Query Format for Export

Hi, What will be the query format to export database table data into different export format (CSV,HTML,XML,SQL) ? Thanks ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users

Re: [sqlite] SQlite3 Query Format for Export

What will be the query format to export database table data into different export format (CSV,HTML,XML,SQL) ? This is not an SQL function. Do you need it exported to some format once, or do you need this often (such as providing it as a standard functionality to users?) If you need it

Re: [sqlite] SQlite3 Query Format for Export

I need this often. If possible provide some hint of plugin in Linux platform. Thanks On Tue, Nov 19, 2013 at 7:01 PM, RSmith wrote: > > What will be the query format to export database table data into different >> export format (CSV,HTML,XML,SQL) ? >> >> > This is not an

Re: [sqlite] SQlite3 Query Format for Export

Try writing a virtual table module that writes the format you require. E.g. Create virtual table export using export ('',''); Insert into export select from ; -Ursprüngliche Nachricht- Von: techi eth [mailto:techi...@gmail.com] Gesendet: Dienstag, 19. November 2013 14:36 An: R Smith;

Re: [sqlite] SQlite3 Query Format for Export

You might see if the following looks like it would work for you. This is from the BASH command prompt: echo '.dump' | sqlite3 mydatabase.sqlite3 >mydatabase.sql On Tue, Nov 19, 2013 at 7:35 AM, techi eth wrote: > I need this often. > > If possible provide some hint of

Re: [sqlite] SQlite3 Query Format for Export

On Tue, 19 Nov 2013 19:05:55 +0530, techi eth wrote: >I need this often. > >If possible provide some hint of plugin in Linux platform. > >Thanks Have a look at the sqlite3 command line tool: sqlite3 -help and at the .help command in that same command line tool. Of interest

Re: [sqlite] Enable WAL on a QNX system

> > I am starting to believe that WAL is not a viable choice on a QNXsystem. > > > All Blackberry phones and tables use it. It may be so, all Blackberry devices may be using WAL, but on my QNX system I just could not make it work. I haven't made a absolute statement, about SQLite and QNX, I just

Re: [sqlite] Enable WAL on a QNX system

On 19 Nov 2013, at 4:24pm, Sandu Buraga wrote: > I noticed that when PRAGMA main.journal_mode=WAL; statement is executed, > the database file is locked in EXCLUSIVE mode, It's locked into EXCLUSIVE mode if it was in EXCLUSIVE mode when you switched to WAL. But there's

Re: [sqlite] Why must WITHOUT ROWID tables have PRIMARY KEYs?

On Tue, Nov 19, 2013 at 6:35 AM, RSmith wrote: > I also do not think (or imagine) that unique constraints "ought" to be > required - I am saying that in the case of SQLite or any mainstream RDBMS it > becomes necessary to have some unique reference to single out a row should

Re: [sqlite] SQLite server/file-locking scenario

Ok, thanks again for the tips, I'll change the ROLLBACK to END. I'm assuming if I open the file read-only it shouldn't lock, right? I'm using Qt, but I send it a read-only parameter which I assume translates into something like a POSIX open("filename", O_RDONLY); Josh On 19 Nov 2013, at

Re: [sqlite] SQLite server/file-locking scenario

On 19 Nov 2013, at 5:05pm, Joshua Grauman wrote: > Ok, thanks again for the tips, I'll change the ROLLBACK to END. > > I'm assuming if I open the file read-only it shouldn't lock, right? I'm using > Qt, but I send it a read-only parameter which I assume translates into >

Re: [sqlite] Enable WAL on a QNX system

> It's locked into EXCLUSIVE mode if it was in EXCLUSIVE mode when you switched to WAL. But > there's nothing requiring it. I was not referring to the locking_mode, I was writing about the lock itself over the database (iNode structure). On QNX the exclusive locking_mode it is required, because

Re: [sqlite] Enable WAL on a QNX system

On 11/20/2013 12:20 AM, Sandu Buraga wrote: It's locked into EXCLUSIVE mode if it was in EXCLUSIVE mode when you switched to WAL. But > there's nothing requiring it. I was not referring to the locking_mode, I was writing about the lock itself over the database (iNode structure). On QNX the

Re: [sqlite] Why must WITHOUT ROWID tables have PRIMARY KEYs?

Hi Nico, thanks for the discussion - although this thread is dangerously close to becoming a stale debate rather than a helpful forum discussion. In this light, I will try to be brief and then fight the urge to reply again. You still seem to try and sell the usability of non-unique tables to

Re: [sqlite] Intended use case for 'without rowid'?

On 18 Nov 2013, at 06:13, Simon Slavin wrote: > On 18 Nov 2013, at 3:38am, Peter Aronson wrote: > >> It might be simpler to simply specify a minimum release of SQLite that must >> be supported, > > Actually this is how lots of apps specify their file

Re: [sqlite] SQLite server/file-locking scenario

Right. I'll go look at the source and confirm or just write it myself using POSIX open() which would be easy. I guess I was just asking what kind of locks you are talking about since I'm not familiar with file locking. In other words, if I did a POSIX open("filename", O_RDONLY); or even

Re: [sqlite] Why must WITHOUT ROWID tables have PRIMARY KEYs?

On Tue, Nov 19, 2013 at 11:50 AM, RSmith wrote: > Hi Nico, thanks for the discussion - although this thread is dangerously > close to becoming a stale debate rather than a helpful forum discussion. > In this light, I will try to be brief and then fight the urge to reply >

Re: [sqlite] Why must WITHOUT ROWID tables have PRIMARY KEYs?

On Mon, Nov 18, 2013 at 5:45 PM, Nico Williams wrote: > Obviously a B-Tree-based table will need *some* key, but it won't need > that key to be UNIQUE. > Yeah it does. Every storage system has a unique key, be it an address in memory or a filename and offset on disk.

Re: [sqlite] SQLite server/file-locking scenario

On 19 Nov 2013, at 6:40pm, Joshua Grauman wrote: > Under what conditions would an open() create a lock that would cause problems? If you did something with it that would interfere with the processes using SQLite's own API. For instance, if you chose options which involved

Re: [sqlite] query optimization

Thanks alot RSmith. On Mon, Nov 18, 2013 at 6:04 PM, d b wrote: > Hi Igor/Keith, > > I tried with both queries. I expect to delete all rows belongs to key 1. > But not deleted. Am I missing something while writing queries? > > delete from emp where key = 1 and (name='' or

Re: [sqlite] Proper handling of SQLITE_BUSY

On Mon, 2013-11-18 at 22:54 -0700, Keith Medcalf wrote: > >Since I run all of these statements withing transactions (between > >"BEGIN" statements and "COMMIT" / "ROLLBACK" statements"), my > >expectation is that SQLITE_BUSY will only ever be returned for > >the leading "BEGIN" statement. > >

[sqlite] 2 more questions

Hi, ALL, 1. I am working with C++ using C API to access the DB. What I did was: upon startup - read the data in the std::vector<>, then use std::sort() to sort this vector appropriately. Now, today it hit me that I can use "ORDER BY" SELECT clause to retrieve data as pre-sorted. What is best