> On 25 May 2012, at 3:04am, IQuant wrote:
>
> > update TICKDATA set IQ_A = ROUND(ASK - (
> > select t2.ASK from TICKDATA t2
> > where t2.SYMBOL = TICKDATA.SYMBOL and t2.TIMESTAMP <
> > TICKDATA.TIMESTAMP ORDER BY T2.SYMBOL, t2.timestamp DESC LIMIT 1),4),
> > IQ_B =
On 5/24/2012 10:17 PM, Andrew Cherednik wrote:
Thanks guys. You really helped me. I think I know what I am going to do. You
see, as I am using a single connection object there is at least one selection
statement executed at the beginning of each process. Then, during the program
lifecycle
Thanks guys. You really helped me. I think I know what I am going to do. You
see, as I am using a single connection object there is at least one selection
statement executed at the beginning of each process. Then, during the program
lifecycle there could be a few updates executed, that use the
On 25 May 2012, at 3:04am, IQuant wrote:
> update TICKDATA set IQ_A = ROUND(ASK - (
> select t2.ASK from TICKDATA t2
> where t2.SYMBOL = TICKDATA.SYMBOL and t2.TIMESTAMP <
> TICKDATA.TIMESTAMP ORDER BY T2.SYMBOL, t2.timestamp DESC LIMIT 1),4),
> IQ_B = ROUND(BID - (
>
Also it suggests that transaction was began as read-only (with a
select statement) and then there was attempt to transform it to a
writing transaction (with insert, update or delete statement) when
there was another writing transaction in progress waiting for this
transaction to finish.
and
On 25 May 2012, at 2:52am, Pavel Ivanov wrote:
> Also it suggests that transaction was began as read-only (with a
> select statement) and then there was attempt to transform it to a
> writing transaction (with insert, update or delete statement) when
> there was another
Thanks for your suggestion Igor Tandetnik:
Scope creep expanded the original query to the actual trading
instruments and the refactored code has evolved to::
update TICKDATA set IQ_A = ROUND(ASK - (
select t2.ASK from TICKDATA t2
where t2.SYMBOL = TICKDATA.SYMBOL and t2.TIMESTAMP <
On Thu, May 24, 2012 at 9:48 PM, Simon Slavin wrote:
>
> On 25 May 2012, at 2:45am, Andrew Cherednik
> wrote:
>
>> Tried different timeouts. The timeouts will basically make the program hang,
>> but eventually the transaction will end
On 5/24/2012 9:41 PM, Andrew Cherednik wrote:
On 5/24/2012 11:36 AM, Igor Tandetnik wrote:
Before first select. Use BEGIN IMMEDIATE instead of regular BEGIN, to start the
transaction.
Thanks. Will do. Do you still believe I need to get rid of the global
connection object?
What do you
On 25 May 2012, at 2:45am, Andrew Cherednik
wrote:
> Tried different timeouts. The timeouts will basically make the program hang,
> but eventually the transaction will end with SQLITE_BUSY error.
Hmm. _BUSY with a timeout of 13 seconds suggests an
On 5/24/2012 11:35 AM, Simon Slavin wrote:
> On 5/24/2012 9:06 PM, Igor Tandetnik wrote:
>
>> What exactly do you mean by "database lockout problems"? What error in what
>> API call are you getting?
>
> I am getting SQLITE_BUSY error very often, and it does not go away, as if the
> database is
On 5/24/2012 11:36 AM, Igor Tandetnik wrote:
> Before first select. Use BEGIN IMMEDIATE instead of regular BEGIN, to start
> the transaction.
Thanks. Will do. Do you still believe I need to get rid of the global
connection object?
___
sqlite-users
On 5/24/2012 9:27 PM, Andrew Cherednik wrote:
Do you use explicit transactions? If yes, do any of those follow the pattern
where you start with a SELECT, and then perform an INSERT or UPDATE or DELETE
(in other words, a transaction starts as a
reader, and then wants to upgrade to a writer)?
On 25 May 2012, at 2:13am, Andrew Cherednik
wrote:
> On 5/24/2012 9:06 PM, Igor Tandetnik wrote:
>
>> What exactly do you mean by "database lockout problems"? What error in what
>> API call are you getting?
>
> I am getting SQLITE_BUSY error very often,
> I believe from the description that this is one single threaded application
> per computer, for N computers, each using a single connection object pointing
> to the same database file on a remote filesystem.
> Therefore, each database access is locking out all the others. Multiple
>
> Are you resetting your prepared statements?
I believe I am resetting all the statements.
> Do you use explicit transactions? If yes, do any of those follow the pattern
> where you start with a SELECT, and then perform an INSERT or UPDATE or DELETE
> (in other words, a transaction starts as a
On 5/24/2012 9:13 PM, Andrew Cherednik wrote:
On 5/24/2012 9:06 PM, Igor Tandetnik wrote:
Actually, scratch that. Multiple statements running on the same connection will
never lock each other out. Are multiple instances of your application running
at the same time, connecting to the
same
I believe from the description that this is one single threaded application per
computer, for N computers, each using a single connection object pointing to
the same database file on a remote filesystem.
Therefore, each database access is locking out all the others. Multiple
connections will
On 5/24/2012 9:06 PM, Igor Tandetnik wrote:
> Actually, scratch that. Multiple statements running on the same connection
> will never lock each other out. Are multiple instances of your application
> running at the same time, connecting to the
> same database?
Yes, they are connecting to the
On 5/24/2012 9:06 PM, Igor Tandetnik wrote:
On 5/24/2012 8:55 PM, Andrew Cherednik wrote:
The program is a multi-user program that runs across the network in
Windows environment. The users constantly experience database lockout
problems. I suspect that it is due to the fact that the sqlite*
On 5/24/2012 8:55 PM, Andrew Cherednik wrote:
The program is a multi-user program that runs across the network in Windows
environment. The users constantly experience database lockout problems. I
suspect that it is due to the fact that the sqlite* object that has been used
for database
On 25 May 2012, at 1:55am, Andrew Cherednik
wrote:
> The program is a multi-user program that runs across the network in Windows
> environment. The users constantly experience database lockout problems. I
> suspect that it is due to the fact that the
Hi,
I have converted a legacy program that has used a Microsoft Jet (Access)
database. The program is written in Visual C++. It is an client-server MFC
application that used OLE-DB interfaces to directly connect to the database. I
have managed to write a drop-in replacement for all the OLE-DB
I tried and got this:
D:\Temp\Test>timethis custom\sqlite3console database.sqlite < query.sql
TimeThis : Command Line : custom\sqlite3console database.sqlite
TimeThis :Start Time : Thu May 24 18:42:51 2012
TimeThis : End Time : Thu May 24 18:42:54 2012
TimeThis : Elapsed Time :
And don't forget /D_CRT_DISABLE_PERFCRIT_LOCKS
And make sure you link with the static library (/MT) not the dynamic runtime.
Visual Studio no longer has a single threaded library. You have to define
_CRT_DISABLE_PERFCRIT_LOCKS in order to get the compiler to generate code and
use library
I've tested your database and query, using the official sqlite3.exe and the
versions I compile myself (Microsoft Visual Studio 2010, x86 and x64):
- Official (x86): ~5s (CPU Time: user 1.965613 sys 2.527216)
- Compiled by me (x86): ~1s (CPU Time: user 1.154407 sys 0.187201)
- Compiled by
On 24 May 2012, at 11:49pm, Nick wrote:
> The sizes of the executable files are almost identical - there's a few
> kilobytes difference.
> I have attached the original (downloaded from sqlite.org) sqlite3.exe,
> a compiled-by-myself sqlite3console.exe. And the source
The sizes of the executable files are almost identical - there's a few
kilobytes difference.
I have attached the original (downloaded from sqlite.org) sqlite3.exe,
a compiled-by-myself sqlite3console.exe. And the source code. Also
there's import tables dump (import tables are also very similar for
On 24 May 2012, at 11:13pm, Nick wrote:
> In my initial message I described some proof-of-concept that I've done.
>
> I downloaded sqlite3.exe (An SQLite command line tool) from the
> SQLite's website. I executed my query and I had to wait 4 seconds for
> it to complete.
I tried defining "SQLITE_TEMP_STORE 2" as well. Unfortunately it
doesn't influence the speed much, in my case...
2012/5/25 Jonas Malaco Filho :
> Why TEMP_STORE=1 (file by default) and not TEMP_STORE=2 (memory by default)?
>
> *Jonas Malaco Filho*
>
> 2012/5/24 Simon
In my initial message I described some proof-of-concept that I've done.
I downloaded sqlite3.exe (An SQLite command line tool) from the
SQLite's website. I executed my query and I had to wait 4 seconds for
it to complete.
Then I downloaded sqlite3.c, sqlite3.h and shell.c, compiled them
Why TEMP_STORE=1 (file by default) and not TEMP_STORE=2 (memory by default)?
*Jonas Malaco Filho*
2012/5/24 Simon Slavin
>
> On 24 May 2012, at 8:59pm, Nick wrote:
>
> > So why does a prebuilt, downloaded from the sqlite website, command
> > line
On 24 May 2012, at 8:59pm, Nick wrote:
> So why does a prebuilt, downloaded from the sqlite website, command
> line tool takes only 4 seconds, while the same tool, built by me,
> takes 4 times longer time to execute?
I'm wondering whether the speed increase is related to
Yes, i have tried it. Here's what sqlite3.exe, that i just built, returns:
sqlite> pragma compile_options ;
TEMP_STORE=1
THREADSAFE=0
sqlite>
Still getting these 14 seconds.
I am using Visual Studio 2008 for building..
2012/5/24 Richard Hipp :
> On Thu, May 24, 2012 at 3:59 PM,
On Thu, May 24, 2012 at 3:59 PM, Nick wrote:
>
> Any way I could make my C program execute this query as fast as the
> prebuilt command line tool does it?
>
Have you tried compiling with the -DSQLITE_THREADSAFE=0 option?
--
D. Richard Hipp
d...@sqlite.org
Hello!
I have a program that does some math in an SQL query. There are
hundreds of thousands rows (some device measurements) in an SQLite
table, and using this query, the application breaks these measurements
into groups of, for example, 1 records, and calculates the average
for each group.
Damien wrote:
>
> It is working for a classic application. But for a website (or a web
> application), the directories x86 and x64 should be in the "~/Bin"
> directory or in "~/" ?
>
The "x86" and "x64" directories should be just inside the directory where
the "System.Data.SQLite.dll" file is
On Thu, May 24, 2012 at 2:04 PM, Simon Slavin wrote:
>
> On 24 May 2012, at 6:56pm, Sidney Cadot wrote:
>
> >> Why risk ending up with an unexpected (possibly old) version
> >> by linking at runtime just to save users less than 300K of disk
> >> space?
>
On 24 May 2012, at 6:56pm, Sidney Cadot wrote:
>> Why risk ending up with an unexpected (possibly old) version
>> by linking at runtime just to save users less than 300K of disk
>> space?
>
> But that's an argument against shared linking in general.
>
> I am just curious
> However, the OP has indicated little that would allow us to guess whether
> his project should follow the norm or not.
I think my question is independent of my particular project; in fact,
I am not working on an SQLite project at the moment.
The reason I asked this question is that I have a
That page appears to specifically be in regards to compiling SQLite from
sources. It means, don't use the individual files, but use the amalgamation
because it's a lot simpler to deal with.
How you compile it, or in what form the compiled object is used is not
mentioned.
-Original
> Why risk ending up with an unexpected (possibly old) version
> by linking at runtime just to save users less than 300K of disk
> space?
But that's an argument against shared linking in general.
I am just curious what idea this particular statement on this
particular help-page (specific to
Thanks everyone!
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sqlite-users mailing list
sqlite-users@sqlite.org
http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
> Yes. SQLite is so small there's really no reason to make a separate library
> of it.
Well, my Linux distribution may provide a "libsqlite3-dev" package,
which makes linking to a recent version of sqlite as simple as adding
LDLIBS=-lsqlite3 to the Makefile. By going that path you ensure that
On May 24, 2012, at 7:22 PM, Mike King wrote:
> Is this Select statement valid?
In SQLite, yes.
> In Oracle, it wouldn't be because
> what is the aggregate of A.
Right. SQLite tries nonetheless to return "something" . A bit of a (mis)feature
IMO.
> Is this behavior defined anywhere?
On Thu, May 24, 2012 at 1:22 PM, Mike King wrote:
> Is this Select statement valid? In Oracle, it wouldn't be because
> what is the aggregate of A. Is this behavior defined anywhere?
>
> create table T (A,B);
> insert into T (A,B) values (1,3);
> insert into T (A,B) values
On Thu, May 24, 2012 at 1:22 PM, Mike King wrote:
> Is this Select statement valid? In Oracle, it wouldn't be because
> what is the aggregate of A. Is this behavior defined anywhere?
>
> create table T (A,B);
> insert into T (A,B) values (1,3);
> insert into T (A,B) values
Is this Select statement valid? In Oracle, it wouldn't be because
what is the aggregate of A. Is this behavior defined anywhere?
create table T (A,B);
insert into T (A,B) values (1,3);
insert into T (A,B) values (2,3);
select A,B
from T
group by B;
On 5/24/2012 11:46 AM, IQuant wrote:
ie. I have a table with 1,000,000 + records collecting real time
stats from many devices with many columns but the main ones of
interest are 'timestamp', 'latency' and 'DeviceID'.
2012-05-01 13:12:11.103 Null 14356
2012-05-01 13:12:11.103 Null 14372
On May 24, Dan Kennedy wrote:
On 05/24/2012 10:53 PM, Larry Brasfield wrote:
>> On the support page http://www.sqlite.org/howtocompile.html, it says:
>>
>> "The use of the amalgamation is recommended for all applications."
>>
>> Is this a general recommendation, to use the amalgamated source
On 05/24/2012 10:53 PM, Larry Brasfield wrote:
On the support page http://www.sqlite.org/howtocompile.html, it says:
"The use of the amalgamation is recommended for all applications."
Is this a general recommendation, to use the amalgamated source file
as the preferred way of including SQLite
On 24 May 2012, at 4:43pm, Sidney Cadot wrote:
> On the support page http://www.sqlite.org/howtocompile.html, it says:
>
>"The use of the amalgamation is recommended for all applications."
>
> Is this a general recommendation, to use the amalgamated source file
> as the
On the support page http://www.sqlite.org/howtocompile.html, it says:
"The use of the amalgamation is recommended for all applications."
Is this a general recommendation, to use the amalgamated source file
as the preferred way of including SQLite functionality in one's
application, rather
How can I construct a update query to calculate and set a record field
"latency" with the difference between "timestamps" by "deviceid"?
Appears sqlite doesn't support lag and lead.
ie. I have a table with 1,000,000 + records collecting real time
stats from many devices with many columns but the
Dear all,
On the support page http://www.sqlite.org/howtocompile.html, it says:
"The use of the amalgamation is recommended for all applications."
Is this a general recommendation, to use the amalgamated source file
as the preferred way of including SQLite functionality in one's
Hi!
Did the call to sqlite3_close() _succeed_? It will fail (iirc) if any
statements are still open.
- stephan beal
http://wanderinghorse.net/home/stephan/
http://gplus.to/sgbeal
On May 24, 2012 2:33 PM, "Alfred Sawaya" wrote:
> Hello,
>
> SQLite version 3.7.9
Hello,
SQLite version 3.7.9 2011-11-01 00:52:41
Valgrind reports some memory leaks :
==9709== HEAP SUMMARY:
==9709== in use at exit: 94,248 bytes in 42 blocks
==9709== total heap usage: 1,338 allocs, 1,296 frees, 1,066,595 bytes
allocated
==9709==
==9709== 80 bytes in 1 blocks are
Hi,
It is working for a classic application. But for a website (or a web
application), the directories x86 and x64 should be in the "~/Bin"
directory or in "~/" ?
Thanks.
Damien
2012/5/23 Joe Mistachkin
>
> Rob Richardson wrote:
> >
> > This is the first I have heard
I just wanted to bring this one again up. Unfortunately there was no reaction
from the system.data.sqlite nor from the SQLite maintainers.
I've patched the crypt.c module to ignore the change counter, so it will never
be encrypted. But that's not the best solution. Is there at least a public
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