Randall Skelton <[EMAIL PROTECTED]> writes:
> What is the storage cost of a null entry in a column?
If you have even one, all the rest in that row are free, so your scheme
sounds reasonable.
Null columns are simply not stored. There is a bitmap at the start of
the row with one bit per column, in
On Apr 2, 2004, at 10:39 AM, Bruno Wolff III wrote:
Except for SQL functions which can be inlined, the optimizer can't
optimize what is being done in the function with what is being done
in the select statement. This might be a performance issue depending
on your particular circumstances.
How does
What is the storage cost of a null entry in a column? i.e. does a null
entry of type integer, float8 or text consume the same amount of
storage as one that is filled? I ask because I have satellite data
which is transmitted via a dodgy RF link that drops data packets. This
means I have a num
On Fri, Apr 02, 2004 at 11:08:21AM -0600, [EMAIL PROTECTED] wrote:
> db=> explain analyze select count(*) from messages m, message_recipients r,
> addresses a WHERE r.Message_Key=m.Message_Key AND
> a.Address='[EMAIL PROTECTED]' AND a.Address_Key=r.Recipient AND (
> (m.Message_Date >= '29-MAR-04')
[time to move this to -hackers]
On Fri, 02 Apr 2004 11:16:21 -0500, Tom Lane <[EMAIL PROTECTED]> wrote:
>Manfred Koizar <[EMAIL PROTECTED]> writes:
>> The first step, however, (acquire_sample_rows() in analyze.c) has to
>> read more rows than finally end up in the sample. It visits less than
>> O
Is there a mechanism to execute a function after the user connects to
the database? I would like to set the schema path based on the user's
group membership. It would also be nice to log to a table on
connect/disconnect.
Thanks,
John DeSoi, Ph.D.
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On 4/1/04 6:00 PM, "Manfred Koizar" <[EMAIL PROTECTED]> wrote:
> And what are your settings for random_page_cost, effective_cache_size,
> and sort_mem?
I didn't read close enough last time. Random_page_cosst, cpu_tuple_cost,
cpu_index_tuple_cost, and cpu_operator_cosst are all at default.
Effect
Manfred Koizar <[EMAIL PROTECTED]> writes:
> The first step, however, (acquire_sample_rows() in analyze.c) has to
> read more rows than finally end up in the sample. It visits less than
> O(nblocks) pages but certainly more than O(1).
> A vague feeling tries to tell me that the number of page rea
On Thu, Apr 01, 2004 at 13:21:15 -0800,
Marc Durham <[EMAIL PROTECTED]> wrote:
> From: "John DeSoi" <[EMAIL PROTECTED]>
>
> Do you think this would work?
> There are a lot of joins. And I assumed it would need to look up the
> parent's and teacher's usernames, and that your many-to-many relatio
On Thu, 01 Apr 2004 12:22:58 +0200, I wrote:
>BTW, ANALYSE is basically a constant time operation.
On closer inspection, this is not the whole truth. ANALY[SZ]E is a two
stage process: First it collects a sample of rows, then these rows are
examined to produce various statistics.
The cost of th
On Thu, Apr 01, 2004 at 22:50:48 -0500,
John DeSoi <[EMAIL PROTECTED]> wrote:
>
> Comments/criticisms about design or performance issues?
Except for SQL functions which can be inlined, the optimizer can't
optimize what is being done in the function with what is being done
in the select statemen
Sean Chittenden <[EMAIL PROTECTED]> writes:
> Does the optimizer optimize away the foreign key checks on a primary
> key if its value doesn't change, even though it's had a value assigned
> to it?
The optimizer has nothing to do with this, but in most cases the foreign
key triggers themselves wi
hello
i see that each table has an oid
but the columns ??
is there an columnoid ?
sylvain
smime.p7s
Description: S/MIME Cryptographic Signature
Alexander Cohen wrote:
> i will get them back in the following order in the tuples:
> Alex
> Barbara
> Cohen
> alex
>
> But i want them back likke this:
> Alex
> alex
> Barbara
> Cohen
Set your locale to something other than C.
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Sky wrote:
HI everybody !
I have a problem, but I don't know the solution:
CREATE TABLE person(
user_id SERIAL NOT NULL,
uid CHARACTER(20) NOT NULL,
pwd CHARACTER(20) NOT NULL,
PRIMARY KEY (user_id)
);
OK, That's right...
CREATE FUNCTION getuserid (CHARACTER(20),CHARACTER(20))
RETURNS SETOF
On 2/4/04 4:50 am, "John DeSoi" <[EMAIL PROTECTED]> wrote:
> Marc,
>
> On Apr 1, 2004, at 4:21 PM, Marc Durham wrote:
>
>> Do you think this would work?
>> There are a lot of joins. And I assumed it would need to look up the
>> parent's and teacher's usernames, and that your many-to-many
>> rel
Does the optimizer optimize away the foreign key checks on a primary
key if its value doesn't change, even though it's had a value assigned
to it? Here's the example:
CREATE TABLE t1 (
i INT PRIMARY,
j TEXT
);
CREATE TABLE t2 (
i INT,
k INT8,
FOREIGN KEY(i) REFERENCES t1(i)
);
INSERT
Hello All,
I built postgresql on HPUX IPF(11.22) platform. It works fine. But I
have warning message "could not
resolve "localhost": host nor service provided, or not known"when I start the
postmaster. I have given
entries in pg_hba.conf file to access also.
$ ./post
Hi,
I want to upgrade glibc on one of my box.. and i have installed postgres via
source.. just incase I updated the glibc do I have to recompile postgres?
TIA,
jm
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Sky <[EMAIL PROTECTED]> writes:
> uid CHARACTER(20) NOT NULL,
> pwd CHARACTER(20) NOT NULL,
Incidentally, are you sure you want character(20) ? The input will be padded
out to 20 characters with spaces. Usually people find varchar() more
convenient.
--
greg
---(en
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