比方说我有“问题群”如何保持共同的父母表的参照完整性?
GroupID | value --------+------ 42 | How often do you 9071 | Other question ...
一个表,并为每个小组的问题,我有“问题”和“可能的答案”
Group | QuestionID | value ------+------------+------ 42 | 5 | ... brush your teeth? 42 | 89 | ... go to the movies? 9071 | 709 | ... another question ... ...
Group | Answer | value ------+--------+------ 42 | 134 | several times per day 42 | 135 | twice a day 42 | 71 | once a day 42 | 803 | every other day 42 | 8 | once a week 42 | 666 | once a month ...
现在,在PHP/HTML中,我做了一个(虚拟)完整的跨组问题和42组可能的答案以构建一个2入口表,用户将在其中选择他/她的答案(HTML version)
How often do you | N/d | 2/d | 1/d | d*2 | 1/w | 1/m | ----------------------+-----+-----+-----+-----+-----+-----+ ... brush your teeth? | () | (X) | () | () | () | () | ... go to the movies? | () | () | () | () | (X) | () |
我知道我需要
insert into answers (question, answer, ...) values (5, 135, ...)
牙齿
和
insert into answers (question, answer, ...) values (89, 8, ...)
电影
的问题是:有没有办法强制执行,这两个问题和答案,在answers
表, “属于”同一组问题?
我想这
insert into answers (question, answer, ...) values (709, 71, ...)
被禁止的,因为问题709“属于”组9071和回答71属于组42
如果我理解正确,你需要在答案表**上有一个**约束,该约束表明答案的组等于问题的组。检查你的数据库帮助,看看如何精确地写这个... – KLE