TypeORM Entity

TypeORM Entity @Entity() 依赖注入 / 注解 / 修饰器 PostgreSQL TypeScript

TypeORM Entity

Entity

Entity is a class that maps to a database table when using SQL database(or collection when using MongoDB).

​​https://orkhan.gitbook.io/typeorm/docs/entities​​

@Entity()

依赖注入 / 注解 / 修饰器

You can create an entity by defining a ​​new class​​ and mark it with ​​@Entity()​​:

// step 1, 创建一个实体

import {
  Entity, 
  PrimaryGeneratedColumn, 
  Column,
} from "typeorm";


@Entity()
export class User {
    @PrimaryGeneratedColumn()
    id: number;
    @Column()
    firstName: string;
    @Column()
    lastName: string;
    @Column()
    isActive: boolean;
}

register entity

Each entity must be registered in your connection options:

// step 2, 注册一个实体
import {createConnection, Connection} from "typeorm";
import {User} from "./entity/User";

const connection: Connection = await createConnection({
    type: "mysql",
    host: "localhost",
    port: 3306,
    username: "test",
    password: "test",
    database: "test",
    entities: [User]
});

you can specify the whole directory with all entities inside - and all of them will be loaded:

// step 2, 注册一组实体
import {createConnection, Connection} from "typeorm";

const connection: Connection = await createConnection({
    type: "mysql",
    host: "localhost",
    port: 3306,
    username: "test",
    password: "test",
    database: "test",
    entities: ["entity/*.js"], // * 通配符
});

alias 别名

If you want to use an ​​alternative table name​​ for the ​​User entity​​ you can specify it in @Entity: ​​@Entity("my_users")​​.

If you want to set a base ​​prefix​​ for all database tables in your application you can specify ​​entityPrefix​​ in connection options.

connection options

​​https://orkhan.gitbook.io/typeorm/docs/connection-options​​

mysql / mariadb connection options

postgres / cockroachdb connection options

sqlite connection options

cordova connection options

react-native connection options

nativescript connection options

mssql connection options

mongodb connection options

sql.js connection options

expo connection options

Common connection options

type - Database type. (required)

"mysql", "postgres", "cockroachdb", "mariadb", "sqlite", "cordova", "nativescript", "oracle", "mssql", "mongodb", "sqljs", "react-native".

​​https://orkhan.gitbook.io/typeorm/docs/connection-options#common-connection-options​​

PostgreSQL

postgres

​​https://orkhan.gitbook.io/typeorm/docs/connection-options#postgres-cockroachdb-connection-options​​

Decorators reference

​​https://orkhan.gitbook.io/typeorm/docs/decorator-reference#entity​​

create a database table named "users".

@Entity("users")
export class User {
  //...
}

specify some additional entity options:

• name - table name. If not specified, then table name is generated from entity class name.
• database - database name in selected DB server.
• schema - schema name.
• engine - database engine to be set during table creation (works only in some databases).
• synchronize - entities marked with false are skipped from schema updates.
• orderBy - specifies default ordering for entities when using find operations and QueryBuilder.

@Entity({
    name: "users",
    engine: "MyISAM",
    database: 'example_dev',
    schema: 'schema_with_best_tables',
    synchronize: false,
    orderBy: {
        name: "ASC",
        id: "DESC"
    }
})
export class User {
  //...
}

refs

PostgreSQL

PostgreSQL is a powerful, open source object-relational database system with over 30 years of active development that has earned it a strong reputation for reliability, feature robustness, and performance.

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