Re: Problem with lower() function

Поиск
Список
Период
Сортировка
От Yuva Chandolu
Тема Re: Problem with lower() function
Дата
Msg-id A0F24737FCB34F489EC955D143BDD8510173E12E@exchange-sf1.corp.ebates.com
обсуждение исходный текст
Ответ на Problem with lower() function  (Yuva Chandolu <ychandolu@ebates.com>)
Список pgsql-hackers
Thank you, we figured out that, the query with lower() is taking too long
and we thought it is having some problem. The actual table in our database
has more than 10 million rows and query is taking too long.

Thanks
Yuva


-----Original Message-----
From: Yuva Chandolu 
Sent: Friday, August 09, 2002 3:41 PM
To: 'pgsql-hackers@postgresql.org'
Subject: [HACKERS] Problem with lower() function


Hi, We have a problem with lower() function working differently for two
different data types

table: yuva_test
column_name    data_type
yt_name1    varchar(255)
yt_name2    char(1)

The data is
yt_name1    yt_name2
yuva        F
bharat        F
1234556    F
234        F

etc.

When we run the query "select * from yuva_test
lower(yt_name1)=lower('1234556') and lower(yt_name2)=lower('F')" it takes
forever to return, but if try "select * from yuva_test yt_name1='1234556'
and lower(yt_name2)=lower('F')" it returns immediately.

What is happenning here? Why lower behaving differently for varchar(255) and
char(1), and how to make first query to work without changing schema.

Thanks
Yuva

---------------------------(end of broadcast)---------------------------
TIP 3: if posting/reading through Usenet, please send an appropriate
subscribe-nomail command to majordomo@postgresql.org so that your
message can get through to the mailing list cleanly


В списке pgsql-hackers по дате отправления:

Предыдущее
От: Rod Taylor
Дата:
Сообщение: Re: Proposal: stand-alone composite types
Следующее
От: Scott Shattuck
Дата:
Сообщение: strange performance anomalies