it depends.If you know you will query against emails addresses, you'd better have either separate column or separate table. Otherwise, if the extra email is only some sort of notes, leave them in one column is fine...
你说 separate column,就是设置两个以上的Email字段吗?那岂不是不符合第二范式了?在同一个字段里放两个Email肯定不行啊,因为以后还指着便捷发邮件呢 单独设置表又觉得太麻烦了。难道就没有更好的办法吗。。
who care NF. I am not a DBA but I know most of my DBA don't care NF at all and I don't give a shit to that anyway...you don't want to go for the separate table and you also want to keep your NF compliant...You know you can't have both, what do you want anyway?If storing email is for notification only, put them in one column with the delimiter and let the application takes care others. That sounds good to you?I know, you also will be the programmer. so you don't want to take the extra burden that is supposed to be taken care of by the database, right?Then we come back to the origin...
who care NF. I am not a DBA but I know most of my DBA don't care NF at all and I don't give a shit to that anyway...you don't want to go for the separate table and you also want to keep your NF compliant...You know you can't have both, what do you want anyway?If storing email is for notification only, put them in one column with the delimiter and let the application takes care others. That sounds good to you?I know, you also will be the programmer. so you don't want to take the extra burden that is supposed to be taken care of by the database, right?Then we come back to the origin...
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特别感谢 ACMAIN_CHM 的解释,很清楚!