MySQL-在GROUP BY在场的情况下删除JSON_ARRAYAGG中的重复结果

我有疑问：

SELECT id, JSON_ARRAYAGG(url) AS urlLinks
FROM links
WHERE id=832781
GROUP BY id;

此查询的结果与列

urlinks

中的相同图像URL重复：

["index.html", "index.html", "index.html", "index.html", "index.html"]

我怎样才能只留下唯一的图像URL

["index.html"]

无法从请求中删除分组依据

JSON_ARRAYAGG（）

不支持

DISTINCT

。您可以在子查询中

选择DISTINCT

，然后聚合：

SELECT id, JSON_ARRAYAGG(url) AS urlLinks
FROM (SELECT DISTINCT id, url from links) l
WHERE id=832781
GROUP BY id;

：

WITH links AS (
    SELECT 832781 id, 'index.html' url
    UNION ALL SELECT 832781, 'index.html'
    UNION ALL SELECT 832781, 'page.html'
)
SELECT id, JSON_ARRAYAGG(url) AS urlLinks
FROM (SELECT DISTINCT id, url from links) l
WHERE id=832781
GROUP BY id;

id | urlLinks -----: | :-------------------------- 832781 |[“index.html”、“page.html”] id | urlLinks -----: | :-------------------------- 832781 | ["index.html", "page.html"]