column as primary key and create index
on Id, how does it affect the performance of the two queries?
Regards,
Phanisekahr
From: Dennis Cote [mailto:[EMAIL PROTECTED]
Sent: Thu 4/26/2007 7:52 PM
To: sqlite-users@sqlite.org
Subject: Re: [sqlite] An explanation
B V, Phanisekhar wrote:
Thanks for that Info.
I have another question:
Assume I have a table given below
"CREATE TABLE IF NOT EXISTS Title(Id INTEGER PRIMARY KEY, TitleName
String)"
"CREATE UNIQUE INDEX IF NOT EXISTS TitleIdx ON TitleName"
Now since Id is an integer and a primary key, this wil
l give even better
performance?
Regards,
Phanisekhar
-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Sent: Thursday, April 26, 2007 3:42 PM
To: sqlite-users@sqlite.org
Subject: Re: [sqlite] An explanation?
"B V, Phanisekhar" <[EMAIL PROTECTED]> wrote
"B V, Phanisekhar" <[EMAIL PROTECTED]> wrote:
> How does the index table looks?
>
> Assume the main table to be:
> CREATE TABLE table1 (a INTEGER, b INTEGER)
> Assume there is an index on column a:
> CREATE INDEX index1 ON table1 (a);
>
> Now let's suppose the entries
ching record. Can you explain how this is? Doesn't it will do binary
search on index table?
Regards,
Phani
-Original Message-
From: Dennis Cote [mailto:[EMAIL PROTECTED]
Sent: Tuesday, April 24, 2007 4:06 AM
To: sqlite-users@sqlite.org
Subject: Re: [sqlite] An explanation?
Marco Bam
Thanks a lot for the explanation Dennis, I really appreciate.
---
Marco
On Apr 24, 2007, at 12:35 AM, Dennis Cote wrote:
Marco Bambini wrote:
Database is uniformly distributed, I created it ad hoc just for my
test (sqlite 3.3.12):
Marco,
Another way to think of this is that if your data
Marco Bambini wrote:
Database is uniformly distributed, I created it ad hoc just for my
test (sqlite 3.3.12):
Marco,
Another way to think of this is that if your database contained random
numbers in the range 1-100 for both a and b, then an index on either of
those values would allow sqlite
Marco Bambini wrote:
I know that I can use the ANALYZE command or that I can index both
columns.
I was making some tests and I found that with one index the query is
slower that without any index, so I just trying to understand the
reason... I do not want to run it faster, I already know that
I know that I can use the ANALYZE command or that I can index both
columns.
I was making some tests and I found that with one index the query is
slower that without any index, so I just trying to understand the
reason... I do not want to run it faster, I already know that it is
possible.
Marco Bambini <[EMAIL PROTECTED]> wrote:
> Yes, I know that it is faster ... I just wonder why with one index
> the query is slower that without any index...
Probably because most of the entries in your table
match the term being indexed. In your case, this
likely means that a large fraction of
Marco Bambini wrote:
As a performance test I created a db with 300,000 records, table is:
CREATE TABLE table1 (a INTEGER, b INTEGER)
a query like:
SELECT * FROM table1 WHERE a=5 AND b=11;
takes 0.281 secs.
if I add two indexes:
CREATE INDEX index1 ON table1(a);
CREATE INDEX index2 ON table1(b)
Yes, I know that it is faster ... I just wonder why with one index
the query is slower that without any index...
---
Marco Bambini
On Apr 23, 2007, at 6:31 PM, P Kishor wrote:
On 4/23/07, Marco Bambini <[EMAIL PROTECTED]> wrote:
As a performance test I created a db with 300,000 records, tab
On 4/23/07, Marco Bambini <[EMAIL PROTECTED]> wrote:
As a performance test I created a db with 300,000 records, table is:
CREATE TABLE table1 (a INTEGER, b INTEGER)
a query like:
SELECT * FROM table1 WHERE a=5 AND b=11;
takes 0.281 secs.
if I add two indexes:
CREATE INDEX index1 ON table1(a);
As a performance test I created a db with 300,000 records, table is:
CREATE TABLE table1 (a INTEGER, b INTEGER)
a query like:
SELECT * FROM table1 WHERE a=5 AND b=11;
takes 0.281 secs.
if I add two indexes:
CREATE INDEX index1 ON table1(a);
CREATE INDEX index2 ON table1(b);
the same query is a
14 matches
Mail list logo
