Thread: database encoding with index search problem

database encoding with index search problem

From
"wisan watcharinporn"
Date:
i have problem in database encoding with indexing

case :1
when i initdb -E win874 mydb and create database with createdb -E win874
dbname
and create table emp with index in empname field


i can select sorting name correct in thai alphabet
such select empName from emp order by empName;
but in
select empName from emp where empname like 'xxx%'
it not using index scan , it use seq scan so it may slow in find name

case :2
when i initdb mydb (use default) and create database with createdb -E win874
dbname
and create table emp with index in empname field


i can not select sorting name  correct in thai alphabet
but in
select empName from emp where empname like 'xxx%'
it using index scan , very fast in find name

problem:
how can i configure database that can correct in sorting name and using
index scan in like 'xxxx%' search


using FreeBSD 5.4
postgreql 8.0.

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Re: database encoding with index search problem

From
Richard Huxton
Date:
wisan watcharinporn wrote:
> problem:
> how can i configure database that can correct in sorting name and using
> index scan in like 'xxxx%' search

I think you'll want to read the following then have a quick search of
the mailing list archives for "opclass" for some examples.
   http://www.postgresql.org/docs/8.0/static/sql-createindex.html
   http://www.postgresql.org/docs/8.0/static/indexes-opclass.html

HTH
--
   Richard Huxton
   Archonet Ltd