从一个表中选择数据，检查并从第二个表中提取值

Question

I have a sql query like below, which is selecting values based on if they exist in the questions table and their section_id value falls within a certain range,

SELECT action_id, action_type, action_details, action_int, action_time
        FROM actions
        WHERE user_id = '".$id."'
        AND action_type = 'other'
        AND ( action_details = 'random question'
                OR action_details = 'review')
        AND action_int IN (
            SELECT id
            FROM questions
            WHERE section_id IN (2,3,4,5,6,7,8) )

And I want to expand it to also pull a second column value from the questions table, 'section_id', and join it onto the results.

What is the best way to go about this? Thanks

Answer 1

从查看代码开始，我假设actions.action_int字段与questions.id字段相关，我相信这就是您所要求的：

SELECT actions.action_id, actions.action_type, actions.action_details, actions.action_int, actions.action_time, questions.section_id
FROM actions
JOIN questions
ON actions.action_int = questions.id
WHERE user_id = '".$id."'
AND action_type = 'other'
AND ( action_details = 'random question'
OR action_details = 'review')
AND action_int IN (
SELECT id
FROM questions
WHERE section_id IN (2,3,4,5,6,7,8) )

Answer 2

Based on your use of in in the section_id I believe this left join should work:

SELECT a.action_id, a.action_type, a.action_details, a.action_int, a.action_time, q.section_id 
FROM actions a left join questions q on a.action_int = q.id 
WHERE a.user_id = '".$id."'
    AND a.action_type = 'other'
    AND a.action_details in('random question', 'review') 
    AND q.section_id IN (2,3,4,5,6,7,8);