Re: [sqlite] Avoiding Database Is Locked Error

2010-06-17 Thread Pavel Ivanov
> In my last post I mentioned that I updated my programs so that I can > execute an arbitrary query or update, thus eliminating the need to use > the sqlite command line utility. There really is only one program > accessing the database now. Sorry, I've missed this detail. In this case you are

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-17 Thread Odekirk, Shawn
>> I am not using BEGIN IMMEDIATE, just BEGIN, but I don't think it is a >> problem in my case, since now there really is just one program accessing >> the database. > >Did you forget the message this thread was started from? The sqlite3 >command line utility is a second program, so this could be

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-16 Thread sub sk79
> I'm running on SCO OpenServer so I'm not sure your product would work for me but I'll take a look StepSqlite compiler's Linux target generates shared objects (.so) that should work on virtually all Unix-like systems thanks to ELF format. As an aside, further in SQLite exploration you may find

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-16 Thread Pavel Ivanov
> I am not using BEGIN IMMEDIATE, just BEGIN, but I don't think it is a > problem in my case, since now there really is just one program accessing > the database. Did you forget the message this thread was started from? The sqlite3 command line utility is a second program, so this could be a

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-16 Thread Odekirk, Shawn
Thank you all for your responses. This discussion has grown a lot more than I thought it would. Like I said in my original question, my system is made up of several programs that communicate by sending messages to each other. I have a utility program that can send messages to the programs for

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-15 Thread sub sk79
Hi Shawn, > demonstrate SQLite best > practices, including how to correctly handle error conditions, such as > the database is locked condition? > If you pre-select and then modify, you have to be aware enough to > realize you MUST wrap the whole process in a manual transaction, > and you

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-15 Thread Jay A. Kreibich
On Tue, Jun 15, 2010 at 04:36:15PM +0100, Simon Slavin scratched on the wall: > > On 15 Jun 2010, at 4:23pm, Robert Latest wrote: > > > Instinctively I'd rather first SELECT, store the > > results, finalize the SELECT statement and then get to work on its > > result using the stored data. It's

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-15 Thread Simon Slavin
On 15 Jun 2010, at 4:23pm, Robert Latest wrote: > Instinctively I'd rather first SELECT, store the > results, finalize the SELECT statement and then get to work on its > result using the stored data. It's just that without intermediate > storage it's a bit easier (no need to do any ressource

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-15 Thread Robert Latest
Hello all, > Oh, I completely forgot that people can do that. So, Robert, you case > is exactly the case I was talking about. As Simon said your SELECT > opens read-only transaction and then as you issue your first UPDATE > this transaction have to be converted to writing one. This is a call >

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-14 Thread Pavel Ivanov
>> Do you mean you're making changes as you call SQLite to _step() through the >> results of the SELECT ?  Or do you read all the results of the SELECT into >> memory, then make changes to the database ? > > The former. Oh, I completely forgot that people can do that. So, Robert, you case is

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-14 Thread Simon Slavin
On 14 Jun 2010, at 3:43pm, Robert Latest wrote: > On Mon, Jun 14, 2010 at 4:36 PM, Simon Slavin wrote: > >> Do you mean you're making changes as you call SQLite to _step() through the >> results of the SELECT ? Or do you read all the results of the SELECT into >> memory,

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-14 Thread Jay A. Kreibich
On Mon, Jun 14, 2010 at 09:42:09AM -0400, Pavel Ivanov scratched on the wall: > > This is interesting. I often have situations where I SELECT something > > and then do manipulations (INSERT/DELETE/UPDATE) on the db as I > > iterate through the results. > > > > Is this what you mean by your

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-14 Thread Robert Latest
On Mon, Jun 14, 2010 at 4:36 PM, Simon Slavin wrote: > Do you mean you're making changes as you call SQLite to _step() through the > results of the SELECT ?  Or do you read all the results of the SELECT into > memory, then make changes to the database ? The former. robert

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-14 Thread Simon Slavin
On 14 Jun 2010, at 1:44pm, Robert Latest wrote: > This is interesting. I often have situations where I SELECT something > and then do manipulations (INSERT/DELETE/UPDATE) on the db as I > iterate through the results. Do you mean you're making changes as you call SQLite to _step() through the

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-14 Thread Robert Latest
Thanks, your and Pavel's clarifications have been very helpful. robert ___ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-14 Thread Jay A. Kreibich
On Mon, Jun 14, 2010 at 02:44:02PM +0200, Robert Latest scratched on the wall: > On Fri, Jun 11, 2010 at 5:26 PM, Pavel Ivanov wrote: > > > 1. Ensure that you have no transactions started with SELECT and > > continued with INSERT/DELETE/UPDATE > > This is interesting. I

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-14 Thread Pavel Ivanov
> This is interesting. I often have situations where I SELECT something > and then do manipulations (INSERT/DELETE/UPDATE) on the db as I > iterate through the results. > > Is this what you mean by your statement? If yes, how should such > situations be avoided, and why? If you issue BEGIN

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-14 Thread Robert Latest
On Fri, Jun 11, 2010 at 5:26 PM, Pavel Ivanov wrote: > 1. Ensure that you have no transactions started with SELECT and > continued with INSERT/DELETE/UPDATE This is interesting. I often have situations where I SELECT something and then do manipulations (INSERT/DELETE/UPDATE)

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-11 Thread Simon Slavin
On 11 Jun 2010, at 4:33pm, Jay A. Kreibich wrote: > For what it is worth, "Using SQLite" has four or five pages > specifically dealing with SQLITE_BUSY errors-- both how to avoid them > and how to correctly handle them. Well, that somewhat increased the chances that I'll check out that book.

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-11 Thread Jay A. Kreibich
On Fri, Jun 11, 2010 at 04:04:59PM +0100, Simon Slavin scratched on the wall: > > On 11 Jun 2010, at 2:50pm, Odekirk, Shawn wrote: > > > Also, are there any code examples that demonstrate SQLite best > > practices, including how to correctly handle error conditions, such as > > the database is

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-11 Thread Pavel Ivanov
>> Also, are there any code examples that demonstrate SQLite best >> practices, including how to correctly handle error conditions, such as >> the database is locked condition? I have been unable to find complete >> code examples. > > Can I point out that this is yet another person asking for the

Re: [sqlite] Avoiding Database Is Locked Error

2010-06-11 Thread Simon Slavin
On 11 Jun 2010, at 2:50pm, Odekirk, Shawn wrote: > Also, are there any code examples that demonstrate SQLite best > practices, including how to correctly handle error conditions, such as > the database is locked condition? I have been unable to find complete > code examples. Can I point out

[sqlite] Avoiding Database Is Locked Error

2010-06-11 Thread Odekirk, Shawn
I have recently upgraded an old system that managed its data in a dynamically allocated linked list to use SQLite instead. I have been extremely pleased with SQLite. Most operations have been greatly simplified and I am much more confident in the stability of the system and the integrity of the