[sqlite] Strange case in 3.2.7 , why Index create on multiple column isn't faster than index created on Single column

I have a Table with about 800,000 record DB Version : 3. 2. 7 The Sql looks like select x, y, sum(z)/1000 as bw from aa where a=1 and b=1 and c =1 and d= 6 group by x, y having count(*) > 1 order by bw desc limit 10 Column "d" is all set to 6 1/3 of

[sqlite] 回复： [sqlite] Re: 回复： [sq lite] Re: About Index using

x,y are both column of Table "aa", they may have random value . And you think that will affect the performance.? What I think is Sqlite will first use "where cluase" to get limited value ,then use "group by" in the same . so , the perfomance depend "where" clause , correct? Igor

[sqlite] Strange case in 3.2.7 , why Index create on multiple column isn't faster than index created on Single column

I have a Table with about 800,000 record DB Version : 3. 2. 7 The Sql looks like select x, y, sum(z)/1000 as bw from aa where a=1 and b=1 and c =1 and d= 6 group by x, y having count(*) > 1 order by bw desc limit 10 Column "d" is all set to 6 1/3 of

[sqlite] 回复： Re: [sqlite] About Index using

Hi Drh I just found a strange case , can you give me some explaination ? I have a Table with about 800,000 record DB Version : 3. 2. 7 The Sql looks like select x, y, sum(z)/1000 as bw from aa where a=1 and b=1 and c =1 and d= 6 group by x, y having

[sqlite] 回复： Re: [sqlite] About Index using

Hi Nathan I just found a strange case , can you give me some explaination ? I have a Table with about 800,000 record DB Version : 3. 2. 7 The Sql looks like select x, y, sum(z)/1000 as bw from aa where a=1 and b=1 and c =1 and d= 6 group by x, y having

[sqlite] 回复： [sqlite] Re: About Index using

Hi Igor I just found a strange case , can you give me some explaination ? I have a Table with about 800,000 record DB Version : 3. 2. 7 The Sql looks like select x, y, sum(z)/1000 as bw from aa where a=1 and b=1 and c =1 and d= 6 group by x, y having count(*) >

Re: [sqlite] limiting table size?

Since you are using a time your could try using a trigger which deleted the row with the oldest (lowest) time. You would need to have an index on the timestamp. I guess something like timestamp > 0 LIMIT 1 might work. Sean Machin wrote: Hi All, I'm considering using SQLLite for an embedded

Re: [sqlite] implementing editable result sets

Will Leshner wrote: On Dec 20, 2005, at 7:46 AM, John Stanton wrote: I haven't looked closely at the problem, so these are just first ideas extending CM's approach. Basically there should be no reason to perform any analysis of the SQL since that has already been done and the

[sqlite] limiting table size?

Hi All, I'm considering using SQLLite for an embedded project. Some of the data I'd like to store is timestamped sensor readings. I'd like to know if there is a way to configure a table so that it acts like a fixed length FIFO queue, e.g. stores 10,000 records then once full drops off the

[sqlite] unsuscribe

-Message d'origine- De : [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Envoyé : mardi 20 décembre 2005 21:41 À : sqlite-users@sqlite.org Objet : re: [sqlite] multiple Db's and journal file time hit? Thank you for the idea! Tom From: Eduardo

re: [sqlite] multiple Db's and journal file time hit?

Thank you for the idea! Tom From: Eduardo <[EMAIL PROTECTED]> Sent: Tuesday, December 20, 2005 11:21 AM To: sqlite-users@sqlite.org Subject: re: [sqlite] multiple Db's and journal file time hit? At 17:17 19/12/2005, you wrote: >I think I've confused

Re: [sqlite] implementing editable result sets

All the source code is on sourceforge ... http://sourceforge.net/projects/sqlite-dotnet2 - Original Message - From: "Joel Lucsy" <[EMAIL PROTECTED]> To: Sent: Tuesday, December 20, 2005 11:53 AM Subject: Re: [sqlite] implementing editable result sets Can

re: [sqlite] multiple Db's and journal file time hit?

At 17:17 19/12/2005, you wrote: I think I've confused the issue a bit and the aforementioned time hit might be normal given: http://www.sqlite.org/lockingv3.html We are using a separately developed COM DLL interface to Sqlite v3: http://www.sqliteplus.com/ And we can live with the journal

Re: [sqlite] implementing editable result sets

On Dec 20, 2005, at 10:46 AM, Fanda Vacek wrote: If you parse such a simple query like SELECT [*,] bla [, bla] FROM table-name WHERE blabla , you'll get into less troubles than if you play with the rowid trick. All you need is to check if returned colnames can be found in table-name. And

Re: [sqlite] implementing editable result sets

On Dec 20, 2005, at 10:19 AM, Robert Simpson wrote: What I'm left with are the alias names and original database table and column names for all the fields in the query, complete with information on whether or not any field is a primary key, how many different tables are involved in the

Re: [sqlite] implementing editable result sets

Can you share what you changed? On 12/20/05, Robert Simpson <[EMAIL PROTECTED]> wrote: > > My approach in the ADO.NET 2.0 provider was to modify the core engine > slightly. I added a database pragma, which when enabled, directs the > internal generateColumnNames() function in select.c to emit

Re: [sqlite] implementing editable result sets

If you parse such a simple query like SELECT [*,] bla [, bla] FROM table-name WHERE blabla , you'll get into less troubles than if you play with the rowid trick. All you need is to check if returned colnames can be found in table-name. And it is a simple question using PRAGMA

Re: [sqlite] implementing editable result sets

- Original Message - From: "Will Leshner" <[EMAIL PROTECTED]> On Dec 20, 2005, at 7:46 AM, John Stanton wrote: I haven't looked closely at the problem, so these are just first ideas extending CM's approach. Basically there should be no reason to perform any analysis of the SQL

Re: [sqlite] implementing editable result sets

On Dec 20, 2005, at 7:46 AM, John Stanton wrote: I haven't looked closely at the problem, so these are just first ideas extending CM's approach. Basically there should be no reason to perform any analysis of the SQL since that has already been done and the metalanguage generated. My

Re: [sqlite] returning multiple rows from custom functions

Nathan Kurz <[EMAIL PROTECTED]> writes: > On Thu, Dec 15, 2005 at 09:17:48PM +, Andrew McDermott wrote: >> For example, I'm currently computing a histogram in application code for >> a moderately sized table (7+ million rows), but I'm wondering whether it >> would be quicker to get the

Re: [sqlite] implementing editable result sets

I haven't looked closely at the problem, so these are just first ideas extending CM's approach. Basically there should be no reason to perform any analysis of the SQL since that has already been done and the metalanguage generated. My approach would be to prepare the SQL statement and then

[sqlite] Question about Index using

Here is a table and with 2 index creatrf on it . == CREATE TABLE test ( a tinyint, /*range 0-3*/ b tinyint,/*range 0-3*/ c tinyint,/*range 0-3*/ d tinyint,/*range 0-3*/ e tinyint,

Re: [sqlite] Problem in Sqlite installation in Irix

It looks as if you need to download the GNU make and compile it for Irix. Try installing it as "gmake" and then execute gmake instead of make. JS Prettina Louis wrote: hello sir, I am trying to install Sqlite-3.2.7 in Irix 6.5 version OS. As mentioned in the README file, I gave the

Re: [sqlite] Version 3.2.8 and 2.8.17

[EMAIL PROTECTED] wrote: > > The source file 2.8.17.tar.gz available on the download page is only 45 bytes > long. I think that's a bit incomplete. :-) > This is not fixed (I think). -- D. Richard Hipp <[EMAIL PROTECTED]>

[sqlite] Sqlite 3.27 slow than 3.22

Dears, Why Sqlite 3.27 it's more slow than Sqlite 3.22 The next Query in Sqlite 3.22 cost 6.47 seconts and 20.3 seconds on Sqlite 3.27 Table with 732.000 records select strftime('%Y',fecha) as Ano, strftime('%m',fecha) as Mes, sum(Duracion) as Duracion,sum(Costo) as Costo,sum(1) as Cantidad

RE: [sqlite] implementing editable result sets

one idea. run an EXPLAIN fist, and then analyze the query plan. it will tell you if there are more than one tables, and maybe you can get info about aggregate functions and such. of course, there is a cost to this... > -Original Message- > From: Will Leshner [mailto:[EMAIL PROTECTED] >