SQL 65) -CASE WHEN 统计正常用户发送给正常用户邮件失败的概率
异常的邮件概率
http://www.nowcoder.com/questionTerminal/d6dd656483b545159d3aa89b4c26004e
方法）CASE WHEN + GROUP BY
- 结果保留到小数点后面3位(3位之后的四舍五入)
- 按照日期升序排序
SELECT date, ROUND(SUM(CASE type WHEN 'completed' THEN 0 ELSE 1 END)*1.0/ COUNT(type),3 ) FROM email WHERE send_id NOT IN (SELECT id FROM user WHERE is_blacklist = 1) AND receive_id NOT IN (SELECT id FROM user WHERE is_blacklist = 1) GROUP BY date ORDER BY date;
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SQL
投递快手等公司10个岗位
