您好，我需要帮助来计算如何根据存储在MySQL中的CDR日期计算我一天中有多少峰值并发调用。数据集如下所示:INSERTINTO`cdr`(`calldate`,`clid`,`src`,`dst`,`dcontext`,`channel`,`dstchannel`,`lastapp`,`lastdata`,`duration`,`billsec`,`disposition`,`amaflags`,`accountcode`,`uniqueid`,`userfield`)VALUES我可以使用以下查询来计算每个唯一日期有多少条目。SELECTCOUNT(1)ASentries,date

如何一次更新2列？我试过下面的语句，它不起作用:UPDATEexercisesSETtimes_answered=times_answered+1ANDav_answeringTime=av_answeringTime+((av_answeringTime/(times_answered))+?)*(times_answered+1)WHEREname=? 最佳答案 使用逗号代替“AND”:UPDATEexercisesSETtimes_answered=times_answered+1,av_answeringTime=av_an

如何一次更新2列？我试过下面的语句，它不起作用:UPDATEexercisesSETtimes_answered=times_answered+1ANDav_answeringTime=av_answeringTime+((av_answeringTime/(times_answered))+?)*(times_answered+1)WHEREname=? 最佳答案 使用逗号代替“AND”:UPDATEexercisesSETtimes_answered=times_answered+1,av_answeringTime=av_an