在一列数据中持有一个向量 [英] holding a vector with in a column of data

问题描述

我正在创建一个网站，其中一个活动可以包含多个人。所以，我想，嘿！我可以制作一个包含人物的矢量，然后将该矢量放入数据库中供我查看。但我找不到矢量的列类型。任何想法我怎么能做到这一点？

I am creating a website in which multiple people can be included in one activity. so to do this i thought, Hey! i can just make a vector of the people included, then put that vector in the database for me to view whenever. but i cant find a column type for vector. any ideas how i could make this happen?

推荐答案

当你有多个要存储的东西时，你不想把它们存储在一列中。他们应该有自己的行。


把人放进入他们自己的桌子，给那张桌子一把钥匙。


把活动放在进入自己的表并给它一个主键。


然后创建一个链接表，链接哪些人参与哪些活动。此表将包含2列：活动的ID和人员的ID。


如果要检索给定活动的人员，请使用链接/查找表，加入人员表，其中activity-id是您要查找的活动。


研究链接（或加入）表，以及如何使用加入表在一个SQL语句中。


-Frinny

When you have multiple things to store, you don''t want to store them in a column. They should have their own rows.

Put "people" into their own table, give that table a primary key.

Put the "activity" into its own table and give it a primary key.

Then create a link table that links which people are involved in which activity. This table will have 2 columns: the id for the activity and the id to a person.

When you want to retrieve the people for a given activity, use the link/look-up table, joined to the people table where the activity-id is the activity that you are looking for.

Research link (or join) tables, and how to use "JOIN" in an SQL statement.

-Frinny

但是如果我不知道活动中有多少人会怎么样呢。我能够按照一定的顺序放置它们。我想我完全不明白你的意思，（数据库新手）

But what if i dont know how many people are going to be in the activity. and i was to be able to put them in a certain order. i guess i quite dont understand what your saying, (new to database)

你可以使用ORDER BY按特定顺序返回结果。


使用此设计的活动中的人数没有限制。


-Frinny

You can use ORDER BY to return the results in a specific order.

There is no limitation to the number of people in an activity with this design.

-Frinny

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