＃1064-您的SQL語法有錯誤：此查詢出了什么問題？

Question

請看下面的查詢。

SELECT sub_words.idwords, words_inc.idArticle
(
    SELECT sub0.idwords, SUBSTRING_INDEX(GROUP_CONCAT(sub1.idwords), ',', 10) AS excl_words,        COUNT(sub1.idwords) AS older_words_cnt
    FROM words_learned sub0
    LEFT OUTER JOIN words_learned sub1
    ON sub0.userId = sub1.userId
    AND sub0.order < sub1.order
    WHERE sub0.userId = 1
    GROUP BY sub0.idwords
) sub_words
INNER JOIN words words_inc
ON sub_words.idwords = words_inc.idwords
LEFT OUTER JOIN words words_exc
ON words_inc.idArticle = words_exc.idArticle
AND FIND_IN_SET(words_exc.idwords, sub_words.excl_words)
WHERE words_exc.idwords IS NULL
ORDER BY older_words_cnt
LIMIT 100 

這給出了錯誤

＃1064-您的SQL語法有誤； 檢查與您的MySQL服務器版本對應的手冊以獲取正確的語法，以在第3行的'SELECT sub0.idwords，SUBSTRING_INDEX（GROUP_CONCAT（sub1.idwords），'，'，10）AS exc'附近使用

我單獨檢查了子查詢，並且子查詢中沒有錯誤！ 這里發生了什么？

Answer 1

您錯過了from關鍵字

SELECT sub_words.idwords, words_inc.idArticle
FROM
( ...