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How to use LEFT JOIN in this query

开发者 https://www.devze.com 2023-02-10 17:24 出处:网络
I have the following query SELECT interview_content.title `title`, gallery_images.img_path img FROM `interview`,

I have the following query

SELECT
    interview_content.title `title`,
    gallery_images.img_path img
FROM
    `interview`,
    `interview_content`,
    `gallery`,
    `gallery_images`
WHERE
    `gallery_images`.`id_parrent` = `gallery`.`id`
AND
    `gallery`.`id` =  `interview`.`gallery_id`
AND
    `gallery_images`.`default` = '1'
AND
    `interview`.`id` = `interview_content`.`id_parrent`
AND
    interview_content.id_lang = '2'
ORDER BY
    interview.date DESC

I need to use LEFT JOIN on gallery, gallery_images tables (to be able to get interview.title even when there is no gallery or default image)

Thanks much

UPDATE


The problem, is in second LEFT JOIN. I can't make them to work together correctly. When i try

SELECT
    interview_content.title `title`,
    gi.img_path img
FROM
    `interview`,
    `interview_content`
LEFT JOIN `gallery` as g ON g.`id` = `interview`.`gallery_id` 
LEFT JOIN `gallery_images` as gi ON gi.id_parrent = g.`id`
WHERE
    `interview`.`id` = `interview_content`.`id_parrent`
AND
    interview_content.id_lang = '2'
ORDER BY
    intervie开发者_如何学Gow.date DESC

it returns //Unknown column 'interview.gallery_id' in 'on clause'


You know what you need to do. Google is your friend?

http://en.wikipedia.org/wiki/Join_%28SQL%29#Left_outer_join


Try that one:

SELECT
    interview_content.title `title`,
    gallery_images.img_path img
FROM
    `interview`,
    `interview_content`,
LEFT JOIN `gallery` ON (`interview`.`gallery_id` = `gallery`.`id` AND `gallery_images`.`default` = '1'), 
LEFT JOIN `gallery_images` ON `gallery`.`id` = `gallery_images`.`id_parrent`
WHERE
    `interview`.`id` = `interview_content`.`id_parrent`
AND
    interview_content.id_lang = '2'
ORDER BY
    interview.date DESC;


Don't mix ANSI-89 style and ANSI-92 style joins.

I found same question in SO, here.

So my query must look like this

SELECT
    ic.title `title`,
    gi.img_path img
FROM
    `interview` i
JOIN interview_content ic  on ic.id_parrent =  i.id AND ic.id_lang = '2'
LEFT JOIN `gallery` as g ON g.`id` = i.`gallery_id` 
LEFT JOIN `gallery_images` as gi ON gi.id_parrent = g.`id`
AND gi.`default` = '1'
WHERE
    i.`id` = ic.`id_parrent`
OPRDER BY
    `i`.`date` DESC
0

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