Thanks and Regards
Yan Cheng CHEOK

--- On Tue, 1/26/10, Alban Hertroys <[email protected]> wrote:

> From: Alban Hertroys <[email protected]>
> Subject: Re: [GENERAL] Primary Key Increment Doesn't Seem Correct Under Table 
> Partition
> To: "Yan Cheng Cheok" <[email protected]>
> Cc: [email protected]
> Date: Tuesday, January 26, 2010, 6:36 PM
> On 26 Jan 2010, at 11:00, Yan Cheng
> Cheok wrote:
> 
> > However, whenever I insert row into measurement table,
> I realize its primary key value is going from 2, 4, 6, 8,
> 10...
> > 
> > May I know how can I prevent this?
> 
> Apparently nextval on that sequence gets called multiple
> times in your queries.
> 

Do you have any idea why it happens so?

> > Also, is it necessary to create index for
> measurement_id found in measurement's child table? I am
> concern on the read speed.
> 
> 
> Serials don't create indexes, only a sequence. Primary keys
> create indexes (to guarantee uniqueness) - foreign keys do
> not.
> So yes, you want an index on that column in the child
> table.
> 

But...

measurement table does contains

CONSTRAINT pk_measurement_id PRIMARY KEY (measurement_id),

when measurement_0 child table inherits from measurement table, isn't it will 
inherit PRIMARY KEY (measurement_id)?

Do I still have to create index for measurement_0.measurement_id ?

> Alban Hertroys
> 
> --
> Screwing up is the best way to attach something to the
> ceiling.
> 
> 
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> 
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