如何在MySQL中存储数组? [英] How to store arrays in MySQL?

问题描述

我在MySQL中有两个表.表人具有以下列:

I have two tables in MySQL. Table Person has the following columns:

id | name | fruits

fruits列可以包含null或字符串数​​组，例如('apple'，'orange'，'banana')或('strawberry')等.第二个表是Table Fruit，具有以下内容三栏:

The fruits column may hold null or an array of strings like ('apple', 'orange', 'banana'), or ('strawberry'), etc. The second table is Table Fruit and has the following three columns:

____________________________
fruit_name | color  | price
____________________________
apple      | red    | 2
____________________________
orange     | orange | 3
____________________________
...,...

那么我应该如何设计第一个表中的fruits列，以便它可以容纳从第二个表中的fruit_name列中获取值的字符串数组?由于MySQL中没有数组数据类型，该怎么办?

So how should I design the fruits column in the first table so that it can hold array of strings that take values from the fruit_name column in the second table? Since there is no array data type in MySQL, how should I do it?

推荐答案

执行此操作的正确方法是使用多个表，并在查询中使用JOIN它们.

The proper way to do this is to use multiple tables and JOIN them in your queries.

例如:

CREATE TABLE person (
`id` INT NOT NULL PRIMARY KEY,
`name` VARCHAR(50)
);

CREATE TABLE fruits (
`fruit_name` VARCHAR(20) NOT NULL PRIMARY KEY,
`color` VARCHAR(20),
`price` INT
);

CREATE TABLE person_fruit (
`person_id` INT NOT NULL,
`fruit_name` VARCHAR(20) NOT NULL,
PRIMARY KEY(`person_id`, `fruit_name`)
);

person_fruit表针对与某人相关联的每个水果包含一行，并有效地将person和fruits表链接在一起，即.

The person_fruit table contains one row for each fruit a person is associated with and effectively links the person and fruits tables together, I.E.

1 | "banana"
1 | "apple"
1 | "orange"
2 | "straberry"
2 | "banana"
2 | "apple"

要检索一个人及其所有果实时，可以执行以下操作:

When you want to retrieve a person and all of their fruit you can do something like this:

SELECT p.*, f.*
FROM person p
INNER JOIN person_fruit pf
ON pf.person_id = p.id
INNER JOIN fruits f
ON f.fruit_name = pf.fruit_name

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