从多个表格中选择并在一张桌子上写字w3schools

Question

我想从多个表中选择并在一个表上写：

INSERT INTO interest_area (category_id, user_id)
        SELECT category_id FROM category
        WHERE category_name = 'HTML' 
        UNION ALL
        SELECT user_id FROM users
        WHERE first_name = 'Memar';

但写不出来。

Answer 1

将您的查询更改为

INSERT INTO interest_area (category_id, user_id)
    SELECT category_id,user_id FROM category c,users u
    WHERE c.category_name = 'HTML' and u.first_name = 'Memar';