SQL 兩個結果來自兩列中的一列

Question

我在論壇中檢查了一些類似的問題，但我似乎無法讓它正常工作。 我在 phpmyadmin

我需要得到這樣的結果：

參考 | 產品名稱English | 產品名稱法語

阻止我的是在同一列（pl.name）上執行 2 個請求：/

這是我現在的查詢：

SELECT
p.reference AS Reference,

(SELECT pl.name
FROM ps_product p
LEFT JOIN ps_product_lang pl ON (p.id_product = pl.id_product)
WHERE p.active = 1
AND pl.id_lang = 2) AS ENname,

(SELECT pl.name
FROM ps_product p
LEFT JOIN ps_product_lang pl ON (p.id_product = pl.id_product)
WHERE p.active = 1
AND pl.id_lang = 1) AS FRname

FROM ps_product p

Answer 1

您不需要在子查詢中加入：

SELECT p.reference AS Reference,
       (SELECT pl.name
        FROM ps_product_lang pl 
        WHERE p.id_product = pl.id_product AND
              p.active = 1 AND
              pl.id_lang = 2
       ) AS ENname,
       (SELECT pl.name
        FROM ps_product_lang pl 
        WHERE p.id_product = pl.id_product AND
              p.active = 1 AND
              pl.id_lang = 1
       ) AS FRname
FROM ps_product p;

這假設只有一行與子查詢匹配。 如果不是這種情況，您可能需要將結果限制為一行。

Answer 2

SELECT
  p.reference AS Reference,
  pl.name as ENname,
  pf.name as FRname
FROM ps_product p
LEFT JOIN ps_product_lang pl ON (p.id_product = pl.id_product and pl.id_lang = 1)
LEFT JOIN ps_product_lang pf ON (p.id_product = pf.id_product and pf.id_lang = 2)
WHERE p.active = 1

我可能已經切換了英語和法語，但這應該很容易解決....