Hi,
Most of us are aware that SQLite on Linux has problems with NFS mounted
volumes - basically the file locking issue.
If there is a single thread accessing the SQLite DB - and this is
guaranteed - then there is no need to have file locking. So I modified
the code for SQLite and removed all loc
> Daniel:
> Thanks for the suggestion.
> I wasn't aware that the prepare statement gained you that
> much for one-table select queries.
> I use it for multi-100k inserts (along with trans.) and it
> saves quite a bit of time.
> This is my sql for the present problem:
>
> select * from (select
Store the sum instead of the amount, then if you need the amount just use this
amount(0) = sum(0)
amount(t_i) = sum(t_i) - sum(t_(i-1))
This way, if you need to select all amount it only takes O(n).
Insert/delete/update takes longer but you select more often than youi
insert/delete/update.
On 7/
Hi,
Is there any possibility to import files from the local file system and
storing in
sqlite DB.And Is there any export option just to check whether
the loaded file into a table consists of same data as the original file or
not.
Is it possible in sqlite?
If possible,How it will stores fil
michael cuthbertson uttered:
Brannon:
Thank you for your thoughts.
To be clear, the 'optimize for speed' setting in MY release is actually
slower than MY debug version - I know nothing about Ralf's settings.
That issue is separate from SQLiteSpy - I didn't mean to conflate them.
And the issue i
You're better off posting this to the list, as I can't answer specifics
for lack of experience of VxWorks. I'll answer what I can inline...
Vivek R uttered:
Hi Smith,
I have the following doubt in SQLite. Could you please help me regarding
theese...
1. what are the resources required by S
Can you change the alias to a different field name than the source tables?
On 7/20/06, blins <[EMAIL PROTECTED]> wrote:
Hi sqlite-users@sqlite.org,
I use sqliteODBC 0.68 + ADO and SQLite 3.3.6.
I try executing sql:
select t1.field1 as field1, t2.field2 as field2 from table1 t1 left join
tabl
On 7/21/06, Ritesh Kapoor <[EMAIL PROTECTED]> wrote:
I've also removed the Synch-mechanism and increased the SQLite page size
as well as the number of pages to hold in cache.
I understand that all this can cause data loss if the system crashes but
that is tolerable.
What I can't figure out is
Hello everyone,
I'm new on this list and I have only a few months of experience with
SQLITE. I use SQLITE 3.3.6 for Linux with C++.
I'm having a few problems with locking. But before describing the
problem itself, I would like to check if I'm doing something wrong.
That's what I do when I try to
Over NFS you are limited to the bandwidth of your network, probably 1-10
Mb/s. Compare that to the disk speed on your host server, one or two
orders of magnitude better. The NFS link could be up to 50 times slower.
If you want better distributed performance use a DBMS server like
PostgreSQL.
On 7/21/06, Daniel van Ham Colchete <[EMAIL PROTECTED]> wrote:
I'm having problems understanding the SQLite docs. At the 'C/C++
Interface for SQLite Version 3' it says that sqlite3_exec is a wrapper
to 'prepare, finalize, reset' without a step. But a little bit down the
document it says you shou
It is possible to resolve the issue by using the traditional C profiler.
Compile the SQL library with profiling on the different compilers and
measure where the time is spent during execution.
You can also compile some test programs and look at the assembler output
to get an idea of the effic
Jay Sprenkle wrote:
> Here's some example code:
>
> sqlite3*db;
>
> // connect to database
> if ( sqlite3_open( "test.db", &db ) )
> throw "Can't open database";
>
> char* sql;
>
> // two forms of the same sql
> sql = "SELECT one.test1, two.test2"
> " FROM one"
> " INNER JOIN tw
Jay, thank you very much man! That answers a lot. And it showed me that
I was not checking the SQLITE_LOCKED case.
But, from what I can see, if your database is busy or locked you just
stop your program execution, or you will end this function WITHOUT
running neither sqlite3_finalize nor sqlite3_
Hello,
is there a similar program as SQLiteSpy for other platforms
available? I am especially interested in programs running on MacOS X.
Hartwig
Hello to everybody
If I have a table with 100.000 unique words I am wondering if SQLite select
if faster an cheaper (RAM, Processor, etc), or If i have to help SQLite
using a Hash function, and what could be that Hash function?
Thanks.
Cesar David Rodas Maldonado said:
> Hello to everybody
>
> If I have a table with 100.000 unique words I am wondering if SQLite
> select
> if faster an cheaper (RAM, Processor, etc), or If i have to help SQLite
> using a Hash function, and what could be that Hash function?
If you're going to the
Cesar David Rodas Maldonado wrote:
Hello to everybody
If I have a table with 100.000 unique words I am wondering if SQLite
select
if faster an cheaper (RAM, Processor, etc), or If i have to help SQLite
using a Hash function, and what could be that Hash function?
Thanks.
Do you want to selec
Jay Sprenkle wrote:
>> Jay, thank you very much man! That answers a lot. And it showed me that
>> I was not checking the SQLITE_LOCKED case.
>>
>> But, from what I can see, if your database is busy or locked you just
>> stop your program execution, or you will end this function WITHOUT
>> running n
Cesar David Rodas Maldonado wrote:
> Hello to everybody
>
> If I have a table with 100.000 unique words I am wondering if SQLite
> select
> if faster an cheaper (RAM, Processor, etc), or If i have to help SQLite
> using a Hash function, and what could be that Hash function?
>
> Thanks.
>
Cesar,
y
I have not a substring, I have a list of words (stemmed words of several
languages) and i just want to get the Id. The word is unique
I know that, but I would like to know if will be better first transform the
word into a number (a hash function), after that select the number and after
search with the index of the word...
understand?. I am sorry for my english...
On 7/21/06, Daniel van Ham Colchete <[EMAIL PROTECTED]> wrote:
>
That's what I think as well.
But, when you say 'all your suggestions' are you talking about
sqlite3_interrupt too?
That would be useful if you were doing queries where you don't know how long
they will take. All my code is written in a way the queries are short so I would
not have to abort lon
If I were looking up a table with only 100,000 words and wanted it to be
fast -
CASE OF SEARCHING ON WORD
a. If it is a fixed table. Sort into alpha sequence in a flat file,
open and memory map the file and use a binary search. Very simple and
fast and would find your word in a few microseco
Cesar David Rodas Maldonado wrote:
I have not a substring, I have a list of words (stemmed words of several
languages) and i just want to get the Id. The word is unique
In that case the sqlite B-Tree index is about as good as you will get.
just make sure that the word is an index.
Cesar,
in that case Clay Dowling's answer says it all:
it's faster to use an hash as an index preloading all your data into
your RAM memory (without SQLite), but if you don't want to use that
amount of memory then you could use an INDEX that will create a Binary
Tree (=btree) that will make your s
Thanks very much to all of you!
I am doing a project of fulltext with sqlite, and i will share the code when
a i finish...
thanks to all for your help.
On 7/21/06, John Stanton <[EMAIL PROTECTED]> wrote:
Cesar David Rodas Maldonado wrote:
> I have not a substring, I have a list of words (stem
I have a question about os_unix.c
On line 854 inside function sqlite3UnixTempFileName, you declare:
static const char *azDirs[] = {
0,
"/var/tmp",
"/usr/tmp",
"/tmp",
".",
};
I'm guessing this is where sqlite attempts to create a temp copy of the
database it's opening.
chtaylo3 <[EMAIL PROTECTED]> wrote:
> I have a question about os_unix.c
>
> On line 854 inside function sqlite3UnixTempFileName, you declare:
> static const char *azDirs[] = {
> 0,
> "/var/tmp",
> "/usr/tmp",
> "/tmp",
> ".",
> };
>
> I'm guessing this is where sqlite a
>Set the global variable sqlite3_temp_directory to any
>directory you want and it tries that directory first.
Ok, fair enough. But why do you try and open the directory? Why can you
just try and create the tmp file there and deal with it if it's not allowed?
I'm asking becuase I have permissi
Hi Folks,
i
I'm unsure if SQLite provides the functionality I seek.
On a duplicate entry/conflict I would like to retrieve the rowid of the
conflicting entry; by possibly updating columns, or replacing the row
entirely while ensuring the rowid doesn't change.
On an INSERT OR REPLACE it deletes th
Thanks to Christian and John for the pointers regarding compilers.
I have not compiled the sqlite sources myself but have used the supplied
binary.
Could either one you give me some tips for compiling the sqlite sources for
either vs 6 or 8?
John, I will follow your advice on inline functions.
The
Michael,
The guy who produced Sqlitespy is a member of this forum so he can
confirm or debunk my theory as to why you are getting a big difference
in execution time. I suspect that Sqlitespy might be storing the SQL in
its compiled (from sqlite3_prepare) form and when you run it you skip
the
Greetings. I recently installed php 5 on Win 2k3 server (iis 6). I
enabled the pdo and sqlite extensions for sqlite, but using the test script
from
http://www.tanguay.at/installPhp5.php5?step=8 ,
I get error message: "failed to open/create the database." Any ideas?
Thank you,
--
greenshire
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