我将如何创建“多项选择”本地数据库中的列？ [英] How would I create "multiple choice" columns in Local Database?

问题描述

我使用本地数据库第一次与我的WPF项目。我有数据库设置，我连接好的ETC。治疗一些列，我想成为多个选择，在几个值之间或整个值的价值。问题很明显是人为错误会在输入数据时产生拼写错误。

I am using local database for first time with my WPF project. I have the database setup, and I am connecting fine ETC. Ther eare some columns which I want to be multiple choice, either between a few values or a whole bunch of values. Problem is obviously human error will make typos now and then when inputting the data.

如何让数据输入为用户提供多重选择？例如，我有一个名为类别的列，并且目前（这将在以后扩展）我只想允许以下选项：
Bronze
Misc

How would I go about making the data entry give the user a multiple choice? So for example, I have a column called "Category", and at the moment (this will be expanded later) I only want to allow the following options: Bronze Misc

我目前有列设置为nvarchar（50），但是手动输入相同的字符串...不是我想做的TBH ...所以...我可以设置它是否有一个预定义值的列表，它会接受？ ：）

I have the columns set to nvarchar(50) at present, but typing the same string manually constantly... not what I would like to be doing TBH... so... Could I set it so that there are a list of predefined values it will accept? :)

感谢：D

推荐答案

您的表列上的任何复杂性。 在这里查看MSDN
So您的表定义将是：

You can use CHECK constraint of any complexity on your table column(s). Check MSDN here So your table definition would be as:

CREATE TABLE T
(
    Category nvarchar(50) CHECK (Category in ('Bronze','Misc'))
)

将来可能更改的可能值列表，并且您不想更改表定义，则可以使用值列表创建一个单独的表，并使用外键。

If you expect your list of possible values to change in the future and you do not want to change a table definition, you can create a separate table with the list of values and use the foreign key.

CREATE TABLE Categories
(
    Id int PRIMARY KEY,
    CategoryName nvarchar(50)
)

INSERT INTO Categories VALUES (1, 'Bronze'), (2, 'Silver'), (3, 'Misc')

CREATE TABLE T
(
    CategoryId int REFERENCES Categories
)

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