Help with a joined query (MySQL)
Hello can anybody see why this query fails?
SELECT A.idAd, A.ads_in_Cat, A.title, A.currency, A.price,
A.in_dpt, A.description, A.featured FROM ads A
LEFT JOIN featured F ON F.ad = A.idAd
INNER JOIN dept D ON D.id_dept = A.in_dpt
INNER JOIN sub_cat_ad S ON S.id_sub_cat = A.ads_in_Cat
INNER JOIN cat_ad C ON C.idCat_ad = S.from_cat_ad
ORDER BY A.featured DESC LIMIT :limit, :offset
But this one works:
SELECT *FROM ads
LEFT JOIN featured ON featured.ad = ads.idAd
INNER JOIN dept ON dept.id_dept = ads.in_dpt
INNER JOIN sub_c开发者_如何学编程at_ad ON id_sub_cat = ads.ads_in_Cat
INNER JOIN cat_ad ON idCat_ad = sub_cat_ad.from_cat_ad
ORDER BY featured DESC LIMIT :limit, :offset
In the first one, I don't want all columns from the table "ads", the query returns only columns till ...FROM ads A.
If you specify to only select fields from A that's what you get: Only fields from A.
If you want fields from other tables too you have to specify them as well.
SELECT
A.idAd, A.ads_in_Cat, A.title, A.currency, A.price, A.in_dpt, A.description, A.featured,
F.*,
D.*,
S.*,
C.*
FROM ads A
LEFT JOIN featured F ON F.ad = A.idAd
INNER JOIN dept D ON D.id_dept = A.in_dpt
INNER JOIN sub_cat_ad S ON S.id_sub_cat = A.ads_in_Cat
INNER JOIN cat_ad C ON C.idCat_ad = S.from_cat_ad
ORDER BY A.featured DESC LIMIT :limit, :offset
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