如何通过 Ruby 和 mysql2 在 Sequel Pro 中创建/维护 ID 字段 [英] How to create/maintain ID field in Sequel Pro via Ruby and mysql2

问题描述

在 Sequel Pro 中，使用以下语句创建了一个表:

In Sequel Pro, created a table using this statement:

CREATE TABLE dogs(
id INT PRIMARY KEY AUTO_INCREMENT,
name TEXT,
color TEXT
);

由于 id 值是由 MySQL 创建的，我想在 ruby​​ 中设置/创建/维护 id 字段，以便 puts dog.id 不会是空字符串.

Since the id value is being created by MySQL, I would like to set/create/maintain the id field in ruby so that puts dog.id will not be an empty string.

想知道这段代码是否可以实现:

Was wondering if this piece of code would accomplish that:

def new_from_hash(hash)
    Dog.new(hash["name"], hash["color"]).tap {|dog| dog.id = hash["id"]}
end

注意:我不是在跑导轨；只是普通的 ruby​​、gem mysql2 和 Sequel Pro.

NOTE: I am not running rails; just plain ruby, the gem mysql2, and Sequel Pro.

谢谢！

推荐答案

好吧，我相信我终于想通了.

Okay, I believe I finally figured this out.

由于 id 值是由 MySQL 创建的，我想在 ruby​​ 中设置/创建/维护 id 字段，以便 puts dog.id 不会是空字符串."

"Since the id value is being created by MySQL, I would like to set/create/maintain the id field in ruby so that puts dog.id will not be an empty string."

=> 因为 id 值是在 MySQL 中自动分配的，Ruby 无法知道该 id 值是什么，因此调用 dog.id 将返回一个空字符串.

=> because id value is automatically assigned in MySQL Ruby has no way of knowing what that id value is and therefore calling dog.id will return an empty string.

=> 我需要找到一种方法来在 ruby​​ 中映射对象的 id 值，以便它与我将对象插入 MySQL 数据库时自动分配给对象的 id 值相同.

=> I need to find a way to map an objects' id value in ruby such that it is the same as the id automatically assigned to the object when I insert it in MySQL database.

=> 注意创建桌狗的语句:

=> Pay attention to the statement used to create Table dogs:

CREATE TABLE dogs(
id INT PRIMARY KEY AUTO_INCREMENT,
name TEXT,
color TEXT
);

它转换为每个狗创建都有一个 id(自动分配给它)、一个名称和一个颜色.考虑存储狗对象的信息有两种方法:

it translates to each dog create has an id (which is automatically assigned to it), a name, and a color. There are two approaches to thinking of the storage of a dog objects' information:

dog = { "id" => 'some integer', "name" => "simba", "color" => "grey" }

dog = [1, "simba", "grey"]

我通常喜欢使用数组来存储信息，但这次我使用了哈希(因为当我对狗(不是狗)调用 .inspect 时，结果是这样的:

I typically like to use arrays to store information but this time around I used a hash (because when I call .inspect on dog (not Dog) the result is something like this:

#<Dog:0x007fbf74c55068 @name="samba", @color="grey">

这让我想到了一个哈希数据结构:

which makes me think of a hash data structure:

{ "id"=> 1, "name"=>"simba", "color"=>"grey"}

在 Ruby 中，我这样做:

In Ruby, I do this:

def row_hash(hash)
  hash={}
  Dog.new(hash[name], hash[color]).tap { |id| id = hash[id] }
end

其中 hash_row 是指保存每个狗对象属性的行.这基本上让 Ruby 知道每次实例化 Dog 类的新实例时，它应该利用该实例化并将 hash[id] 映射到id".

Where hash_row refers to the row that holds each dog object's attribute. This basically lets Ruby know that each time it instantiates a new instance of the class Dog it should tap into that instantiation and map hash[id] to "id".

这样做允许我访问 ruby​​ 中id"的值.

Doing this allows me to access the value of "id" in ruby.

PS:这只是我突然想到的.我可能会在它渗透一段时间后编辑这个答案.

PS: This just occurred to me. I probably will edit this answer after it percolates for a while.

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