Re: [PERFORM] How to boost performance of queries containing pattern matching characters

2011-02-14 Thread Steve Atkins
On Feb 14, 2011, at 12:09 AM, Artur Zając wrote: >> Looks like you've almost re-invented the trigram module: >> http://www.postgresql.org/docs/9.0/static/pgtrgm.html > > I didn't know about this module. > Idea to use three letters strings and use Full Text Search is the same, but > the rest is

Re: [PERFORM] How to boost performance of queries containing pattern matching characters

2011-02-14 Thread Greg Smith
Gnanakumar wrote: Thanks for your suggestion. Our production server is currently running PostgreSQL v8.2.3. I think pg_trgm contrib module is not available for 8.2 series. You're going to find that most of the useful answers here will not work on 8.2. Full-text search was not fully inte

Re: [PERFORM] How to boost performance of queries containing pattern matching characters

2011-02-14 Thread Shaun Thomas
On 02/14/2011 12:59 AM, Gnanakumar wrote: QUERY: DELETE FROM MYTABLE WHERE EMAIL ILIKE '%domain.com%' EMAIL column is VARCHAR(256). Honestly? You'd be better off normalizing this column and maybe hiding that fact in a view if your app requires email as a single column. Split it like this:

Re: [PERFORM] Field wise checking the performance.

2011-02-14 Thread Heikki Linnakangas
On 14.02.2011 14:06, dba wrote: I have two identical tables. But the with of the fields are different. Need to know whether changing from varchar(100) to varchar(30) will increase the performance, or its just the memory access. It will make no difference. The max length is just a constraint on

[PERFORM] Field wise checking the performance.

2011-02-14 Thread dba
I have two identical tables. But the with of the fields are different. Need to know whether changing from varchar(100) to varchar(30) will increase the performance, or its just the memory access. -- View this message in context: http://postgresql.1045698.n5.nabble.com/Field-wise-checking-the-pe

Re: [PERFORM] performance issue in the fields.

2011-02-14 Thread Pavel Stehule
Hello 2011/2/14 dba : > > > create table a( address1 int,address2 int,address3 int) > create table b(address int[3]) > > I have created two tables. In the first table i am using many fields to > store 3 address. > as well as in b table, i am using array data type to store 3 address.  is > there an

[PERFORM] performance issue in the fields.

2011-02-14 Thread dba
create table a( address1 int,address2 int,address3 int) create table b(address int[3]) I have created two tables. In the first table i am using many fields to store 3 address. as well as in b table, i am using array data type to store 3 address. is there any issue would face in performance rel

Re: [PERFORM] How to boost performance of queries containing pattern matching characters

2011-02-14 Thread Artur Zając
> Looks like you've almost re-invented the trigram module: > http://www.postgresql.org/docs/9.0/static/pgtrgm.html I didn't know about this module. Idea to use three letters strings and use Full Text Search is the same, but the rest is not. Is the idea to use similarity for this problem is real

Re: [PERFORM] How to boost performance of queries containing pattern matching characters

2011-02-14 Thread Gnanakumar
> The closest you can do is something like Artur's option (or the pg_trgm > module - handy since you are looking at 3-chars and up) to select likely > matches combined with a separate search on '%domain.com%' to confirm > that fact. Thanks for your suggestion. Our production server is currentl

Re: [PERFORM] How to boost performance of queries containing pattern matching characters

2011-02-14 Thread Artur Zając
>How can we boost performance of queries containing pattern matching >characters? In my case, we're using a percent sign (%) that matches any string of zero or more characters. > > QUERY: DELETE FROM MYTABLE WHERE EMAIL ILIKE '%domain.com%' > > EMAIL column is VARCHAR(256). > > As it is clear

Re: [PERFORM] choosing the right RAID level for PostgresQL database

2011-02-14 Thread david
On Sun, 13 Feb 2011, Dave Crooke wrote: For any database, anywhere, the answer is pretty much always RAID-10. The only time you would do anything else is for odd special cases. there are two situations where you would opt for something other than RAID-10 1. if you need the space that raid