typeorm：在 postgresql 中自动生成的 UUID
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typeorm: auto generated UUID in postgresql
提问by Neil Stevens
I am writing an REST API and for data access I am using typeorm, I have used this successfully but I would like to have a UUID auto-generated primary key on one of my tables.
我正在编写一个 REST API 并且我正在使用 typeorm 进行数据访问，我已经成功地使用了它，但是我希望在我的一个表上有一个 UUID 自动生成的主键。
Does anyone know how to setup a column in typeorm that is a UUID type and auto-generated, I have tried the following:
有谁知道如何在 typeorm 中设置 UUID 类型和自动生成的列，我尝试了以下操作：
Using @PrimaryGeneratedColumn()
使用 @PrimaryGeneratedColumn()
@PrimaryGeneratedColumn() id: string;
This gives me an exception when synchronising with the database
这在与数据库同步时给了我一个异常
TypeORM connection error: Error: column "id" cannot be cast automatically to type integer
app.ts:65
at new QueryFailedError (/Users/neilstevens/repositories/Capp.co/capp/ms/ms-token-server/node_modules/typeorm/error/QueryFailedError.js:27:28)
at Query.callback (/Users/neilstevens/repositories/Capp.co/capp/ms/ms-token-server/node_modules/typeorm/driver/postgres/PostgresQueryRunner.js:216:38)
at Query.handleError (/Users/neilstevens/repositories/Capp.co/capp/ms/ms-token-server/node_modules/pg/lib/query.js:143:17)
at Connection.connectedErrorHandler (/Users/neilstevens/repositories/Capp.co/capp/ms/ms-token-server/node_modules/pg/lib/client.js:132:26)
at emitOne (events.js:115:13)
at Connection.emit (events.js:210:7)
at Socket.<anonymous> (/Users/neilstevens/repositories/Capp.co/capp/ms/ms-token-server/node_modules/pg/lib/connection.js:118:12)
at emitOne (events.js:115:13)
at Socket.emit (events.js:210:7)
at addChunk (_stream_readable.js:266:12)
Using @PrimaryColumnand @Generated
使用@PrimaryColumn和@Generated
@PrimaryColumn({type:"uuid"})
@Generated("uuid") id: string;
I get the following error when attempting this
尝试此操作时出现以下错误
TypeORM connection error: Error: sequence "SystemUser_id_seq" does not exist
app.ts:65
at new QueryFailedError (/Users/neilstevens/repositories/Capp.co/capp/ms/ms-token-server/node_modules/typeorm/error/QueryFailedError.js:27:28)
at Query.callback (/Users/neilstevens/repositories/Capp.co/capp/ms/ms-token-server/node_modules/typeorm/driver/postgres/PostgresQueryRunner.js:216:38)
at Query.handleError (/Users/neilstevens/repositories/Capp.co/capp/ms/ms-token-server/node_modules/pg/lib/query.js:143:17)
at Connection.connectedErrorHandler (/Users/neilstevens/repositories/Capp.co/capp/ms/ms-token-server/node_modules/pg/lib/client.js:132:26)
at emitOne (events.js:115:13)
at Connection.emit (events.js:210:7)
at Socket.<anonymous> (/Users/neilstevens/repositories/Capp.co/capp/ms/ms-token-server/node_modules/pg/lib/connection.js:118:12)
at emitOne (events.js:115:13)
at Socket.emit (events.js:210:7)
at addChunk (_stream_readable.js:266:12)
So it looks like this way I can get a primary column but typeorm is not creating the sequence required for this to be an auto-generated column.
所以看起来我可以通过这种方式获得主列，但 typeorm 没有创建自动生成列所需的序列。
If I use @PrimaryColumn({type: "uuid"})then I do get a UUID column in the table but NOTand auto-generated column
如果我使用，@PrimaryColumn({type: "uuid"})那么我会在表中得到一个 UUID 列，但不是和自动生成的列
I cannot see any other way to achieve this so could someone please advise if this is a) even possible and b) how one would go about creating a auto-generated UUID column...please?
我看不到任何其他方法来实现这一点，所以有人可以建议这是否 a) 甚至可能 b) 如何创建自动生成的 UUID 列...请？
回答by D.Zotov
Try:
尝试：
@PrimaryGeneratedColumn("uuid")
id: string;
Also, if you don't need a primary column, but need to generate uuid sequence, you can try this:
另外，如果你不需要主列，但需要生成 uuid 序列，你可以试试这个：
@Column()
@Generated("uuid")
uuid: string;
回答by Joshua Manns
As of Typeorm version 0.1.16, the decorator @PrimaryGeneratedColumnsupports uuidfor all databases.
从 Typeorm 版本开始0.1.16，装饰器@PrimaryGeneratedColumn支持uuid所有数据库。
Usage:
用法：
@Entity()
class MyClass {
@PrimaryGeneratedColumn('uuid')
id: string;
}
If your version of Postgres doesn't already include uuid-ossp(used to generate the UUID), you can install it using create extension "uuid-ossp";.
如果您的 Postgres 版本尚未包含uuid-ossp（用于生成 UUID），您可以使用create extension "uuid-ossp";.
回答by Dan
This is what I am using for Postgres 9.6 and 10. UUID is generated by default.
这是我用于 Postgres 9.6 和 10 的。默认情况下生成 UUID。
CREATE EXTENSION pgcrypto;
CREATE TABLE my_table
(
uuid UUID NOT NULL UNIQUE DEFAULT gen_random_uuid()
);
However, I haven't been using the UUID as my primary key. This is here mainly for migration purposes. What I do know is that its unique, and haven't had a collision yet in the development environment. You can try replacing NOT NULL and UNIQUE with PRIMARY KEY instead.
但是，我没有使用 UUID 作为我的主键。这在这里主要用于迁移目的。我所知道的是它的独特性，并且在开发环境中还没有发生冲突。您可以尝试用 PRIMARY KEY 替换 NOT NULL 和 UNIQUE。
