Commands out of sync; you can't run this command now SQL

问题描述：Commands out of sync; you can't run this command now SQL

问题来源：数据库做表跟表连接的时候没有做校验，由于查询返回两个结果集引起的bug，比如我下面这句sql

SELECT r.userId FROM process_run r JOIN process_form f WHERE f.activityName = '开始' AND f.`status` = 1上面这天sql就是缺少了on的校验
SELECT r.userId FROM process_run r JOIN process_form f on r.runId = f.runId WHERE f.activityName = '开始' AND f.`status` = 1

这样子就没有问题，出现这种问题其实都是差不多这个意思！



解决方案：关闭数据库，重新连接就可以了！