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最好使用豆类或var果
原标题:Is it better to use boolean or varchar

I have a table EDUCATION_TRAINING ( SchoolID INT NOT NULL PRIMARY KEY, SchoolName VARCHAR(100) NOT NULL, SchoolAddress VARCHAR (100) NOT NULL, SchoolCountry VARCHAR (100) NOT NULL, AreaofStudy VARCHAR (100) );

but I need to attach an Education type. So I created another table EDUCATIONTYPE (SchoolID int NOT NULL PRIMARY KEY, Undergrad_Training, Masters, Doctorate, Internship, Residency, Fellowship)

但我不敢确定设立这一表格的最佳方式。 我需要挑选一个属性,因为我想的是 b,但这可能导致 red余。 因此,我正在考虑从教育中去除研究区,并在教育计划中使用千禧年(100),这样我们就能够在研究领域打造一个禁区表。 这样做的最佳途径是什么?

诱杀将导致裁员

问题回答

因此,你基本上重新寻找许多关系? 处理这一问题的共同办法是,如你所述,列入一个连接表。

SchoolID int not null
AreaOfStudyId int not null
RowId int not null

该表在教育培训表和“地区研究”表之间,并在两个表之间建立了联系,使你能够有多个学习领域,在很多学校学习。

在某些情况下,电网的运行是必要,在某些情况下,你可以把它包括在内,或像你认为的那样离开。 它并不严格地要求它完成“公平与和解”的工作。

That depends, mostly upon the reports you wish to generate. You need to use VARCHAR and type in the area of study, so you can later group by area of study and just create your required reports. It s not so much about redundancy but rather your usecase.

然而,如果你希望直接投入研究领域,你可能根本不需要单独的表格? 我认为,你可以把研究领域直接添加到<代码>。 Education_Training and abolition of the EducationType table,除非你计划建立一个数百万记录的数据库,Education 类型表是多余的。





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