Re: LIMIT causes planner to do Index Scan using a less optimal index

От: Sherry.CTR.Zhu@faa.gov
Тема: Re: LIMIT causes planner to do Index Scan using a less optimal index
Дата: ,
Msg-id: OFCDCC668F.8735D136-ON852576FE.00496440-852576FE.004980E3@faa.gov
(см: обсуждение, исходный текст)
Ответ на: Re: LIMIT causes planner to do Index Scan using a less optimal index  (Grzegorz Jaśkiewicz)
Ответы: Re: LIMIT causes planner to do Index Scan using a less optimal index  (Matthew Wakeling)
Список: pgsql-performance



Please just let me know if Postgres can do this kind of index or not.  

create index idx1 on tb1(col1, col2)

Then later we can find it is useful or useless.  


Thanks much!

Xuefeng Zhu (Sherry)
Crown Consulting Inc. -- Oracle DBA
AIM Lab Data Team
(703) 925-3192



Grzegorz Jaśkiewicz <>
Sent by:

04/07/2010 09:12 AM

To
Sherry CTR Zhu/AWA/CNTR/FAA@FAA
cc
Joel Jacobson <>, , Robert Haas <>
Subject
Re: [PERFORM] LIMIT causes planner to do Index Scan using a less         optimal index







2010/4/7 <>

Do you mean one index on two columns?


something like this:   create index idx1 on tb1(col1, col2);

yup :) It would be quite useless without that feature.
Don't listen to oracle folks, they obviously know not much about products others than oracle db(s).
 




--
GJ


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