[pgsql-jp: 36985] Re: 副問い合わせを利用したUPDATE

[Kawasaki Yusuke]

川崎です。動作確認してませんが、↓で１回になるかと。

UPDATE tbl_true_data
SET stateprov=sp, cityname=cn, addressline=al, bldgroom=br, countryname=cn
FROM ( SELECT stateprov AS sp, cityname AS cn, addressline AS al,
bldgroom AS br,
    countryname AS cn FROM tbl_web_data WHERE corporation_id = 777 ) AS t1
WHERE corporation_id = 777;

と思ったら、既に別解が入ってますね。どっちが速いかな。

On 4/12/06, ISHIDA Akio <iakio ＠ mono-space.net> wrote:
>
> UPDATE文にはFROM句を指定できます。
> この例だとおそらくこんな感じです。
>
> UPDATE tbl_true_data
>    SET stateprov = w.stateprov
>      , cityname = w.cityname
> ...
>   FROM tbl_web_data AS w
>  WHERE corporation_id = w.corporation_id
>    AND corporation_id = 777

--
Kawasaki Yusuke <u-suke ＠ kawa.net> http://www.kawa.net/