题目一： sql： 计算下表的用户平均停留时长： || userid || actionType || timestamp || =============================== || a || login || 1234567891 || || a || logout || 1234567892 || || b || login || 1234567893 || || a || login || 1234567894 || || b || logout || 1234567895 || || a || logout || 1234567896 || 题目二： sql： 计算用户每人每天的最后一次登录微信的停留时长： the_date,uid,timestamp,stay_time 例子: 20210329,user123,1617012000,600

题目一的SQL查询语句可以如下所示：

SELECT userid, AVG(stay_time) AS avg_stay_time
FROM (
  SELECT userid, timestamp AS login_time,
    LEAD(timestamp) OVER (PARTITION BY userid ORDER BY timestamp) AS logout_time,
    LEAD(timestamp) OVER (PARTITION BY userid ORDER BY timestamp) - timestamp AS stay_time
  FROM your_table
  WHERE actionType = 'login'
) subquery
WHERE logout_time IS NOT NULL
GROUP BY userid;

注意替换 `your_table` 为你的表名。

题目二的SQL查询语句可以如下所示：

SELECT the_date, uid, stay_time
FROM (
  SELECT the_date, uid, timestamp, stay_time,
    ROW_NUMBER() OVER (PARTITION BY the_date, uid ORDER BY timestamp DESC) AS rn
  FROM your_table
) subquery
WHERE rn = 1;

注意替换 `your_table` 为你的表名。

相关问题

MySQL 计算下表的用户平均停留时长： || userid || actionType || timestamp || =============================== || a || login || 1234567891 || || a || logout || 1234567892 || || b || login || 1234567893 || || a || login || 1234567894 || || b || logout || 1234567895 || || a || logout || 1234567896 |

你可以使用以下的SQL语句来计算用户的平均停留时长：

SELECT userid, AVG(logout_time - login_time) AS avg_stay_time
FROM (
    SELECT userid, timestamp AS login_time
    FROM your_table
    WHERE actionType = 'login'
) AS logins
JOIN (
    SELECT userid, timestamp AS logout_time
    FROM your_table
    WHERE actionType = 'logout'
) AS logouts ON logins.userid = logouts.userid
GROUP BY userid;

请将`your_table`替换为你的表名。这个查询首先会筛选出所有的登录记录和退出记录，然后通过内连接将它们匹配起来，并计算每个用户的平均停留时长。

MySQL计算表的用户平均时长，表中字段有userid,actiontype,timestamp

你可以使用以下SQL查询语句来计算表的用户平均时长：

SELECT userid, AVG(timestamp) AS average_duration
FROM your_table
GROUP BY userid;

这条查询语句会按照userid分组，并计算每个用户的平均时间戳。你可以将"your_table"替换为你实际使用的表名。请确保该表中包含userid、actiontype和timestamp字段。查询结果将返回每个用户的userid和平均时长。

如果你想要进一步筛选特定的actiontype，可以在查询语句中添加WHERE子句，例如：

SELECT userid, AVG(timestamp) AS average_duration
FROM your_table
WHERE actiontype = 'your_actiontype'
GROUP BY userid;

将"your_actiontype"替换为你想要筛选的具体actiontype。这样，查询结果将仅包含该actiontype的用户平均时长。