From: Zheng Yang <zhengyang4k@gmail.com>
To: Guillaume Lelarge <guillaume@lelarge.info>
Cc: Selena Deckelmann <selena@chesnok.com>
Cc: Andrew Dunstan <andrew@dunslane.net>
Cc: pgsql-students@postgresql.org
Subject: Re: foreign data wrappers
Date: Thu, 24 Mar 2011 16:49:19 +0800
Message-ID: <4ACC318A-1B6F-49A5-9B02-49EEAF7B97C7@gmail.com> (raw)
In-Reply-To: <4D8AF8C2.3000007@lelarge.info>
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Hi Guillaume,
Thanks very much! Your answers help a lot!
>
> Le 24/03/2011 06:39, Zheng Yang a écrit :
>
>> 4) Is theFDW something similar to the Mysql storage engine architecture?
>>
>
> Not really.
AFAIK,there is a CSV storage engine in MySql that serves as a wrapper, enable executing SQL queries directly on the file.
This makes me think that the CSV FDW was doing similar things.
>
>> 5) for the datalink, the doc has mentioned about it's going to be OS dependent. but i dun quite understand how does the kernel module and LD_PRELOAD will work in this case, esp.LD_PRELOAD.
>>
>
> No idea.
>
I am quite new to postgresql, but slowly picking up :) In general context, storing images directly inside DBMS fields as BLOBs was not considered as a good practice.
However, storing file directories or links may cause inconsistency. So I am quite interested in how this datalink concept can be implemented!
> Writing some FDWs would make a really good GSoC project.
Haha, agree! I believe that's also a great starting point for learning pgsql internals.
cheers
ZY
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To: pgsql-general@postgresql.org
Cc: zhengyang4k@gmail.com, guillaume@lelarge.info, selena@chesnok.com, andrew@dunslane.net, pgsql-students@postgresql.org
Subject: Re: foreign data wrappers
In-Reply-To: <4ACC318A-1B6F-49A5-9B02-49EEAF7B97C7@gmail.com>
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