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tachybase_todo/docs/en-US/api/database/repository.md
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Repository

Overview

On a given Collection object, you can get its Repository object to perform read and write operations on the data table.

const { UserCollection } = require("./collections");

const UserRepository = UserCollection.repository;

const user = await UserRepository.findOne({
  filter: {
    id: 1
  },
});

user.name = "new name";
await user.save();

Query

Basic Query

On the Repository object, call the find* methods to perform query. The filter parameter is supported by all query methods to filter the data.

// SELECT * FROM users WHERE id = 1 
userRepository.find({
  filter: {
      id: 1
  }
});

Operator

The filter parameter in the Repository also provides a variety of operators to perform more diverse queries.

// SELECT * FROM users WHERE age > 18
userRepository.find({
  filter: {
    age: {
      $gt: 18
    }
  }
});

// SELECT * FROM users WHERE age > 18 OR name LIKE '%张%'
userRepository.find({
  filter: {
    $or: [
      { age: { $gt: 18 } },
      { name: { $like: "%张%" } }
    ]
  }
});

Refer to Filter Operators for more details on operators.

Field Control

Control the output fields by the fields, except, and appends parameters when performing query.

  • fields: Specify output fields
  • except: Exclude output fields
  • appends: Append output associated fields
// The result contains only the <i>id</i> and <i>name</i> fields
userRepository.find({
  fields: ["id", "name"],
});

// The result does not contain only the <i>password</i> field
userRepository.find({
  except: ["password"],
});

// The result contains data associated with the <i>posts</i> object
userRepository.find({
  appends: ["posts"],
});

Associated Field Query

The filter parameter supports filtering by associated fields, for example:

// Find the <i>user</i> objects whose associated posts have title of "post title"
userRepository.find({
  filter: {
      "posts.title": "post title"
  }
});

Associated fields can also be nested:

// Find the <i>user</i> objects whose associated posts have comments containing "keywords"
await userRepository.find({
  filter: {
    "posts.comments.content": {
      $like: "%keywords%"
    }
  }
});

Sort

Sort query results by the sort parameter.


// SELECT * FROM users ORDER BY age
await userRepository.find({
  sort: 'age'
});


// SELECT * FROM users ORDER BY age DESC
await userRepository.find({
  sort: '-age'
});

// SELECT * FROM users ORDER BY age DESC, name ASC
await userRepository.find({
  sort: ['-age', "name"],
});

Sort by the field of the associated object is also supported:

await userRepository.find({
  sort: 'profile.createdAt'
});

Create

Basic Create

Create new data objects via Repository.


await userRepository.create({
  name: "Mark",
  age: 18,
});
// INSERT INTO users (name, age) VALUES ('Mark', 18)


// Bulk creation
await userRepository.create([
  {
    name: "Mark",
    age: 18,
  },
  {
    name: "Alex",
    age: 20,
  },
])

Create Association

Create associated objects at the same time of creating data. Similar to query, nested use of associated objects is also supported. For example:

await userRepository.create({
  name: "张三",
  age: 18,
  posts: [
    {
      title: "post title",
      content: "post content",
      tags: [
        {
          name: "tag1",
        },
        {
          name: "tag2",
        },
      ],
    },
  ],
});
// When crearing a user, creat a post to associate with the user, and create tags to associate with the post

If the associated object is already in the database, you can pass its ID to create an association with it.

const tag1 = await tagRepository.findOne({
  filter: {
    name: "tag1"
  },
});

await userRepository.create({
  name: "Mark",
  age: 18,
  posts: [
    {
      title: "post title",
      content: "post content",
      tags: [
        {
          id: tag1.id,  // Create an association with an existing associated object
        },
        {
          name: "tag2",
        },
      ],
    },
  ],
});

Update

Basic Update

After getting the data object, you can modify the properties directly on the data object (Model), and then call the save method to save the changes.

const user = await userRepository.findOne({
  filter: {
    name: "Mark",
  },
});


user.age = 20;
await user.save();

The data object Model is inherited from Sequelize Model, refer to Sequelize Model for the operations on Model.

Or update data via Repository:

// Update the records that meet the filtering condition
await userRepository.update({
  filter: {
    name: "Mark",
  },
  values: {
    age: 20,
  },
});

Control which fields to update by the whitelist and blacklist parameters, for example:

await userRepository.update({
  filter: {
    name: "Mark",
  },
  values: {
    age: 20,
    name: "Alex",
  },
  whitelist: ["age"], // Only update the <i>age</i> field
});

Update Associated Field

Associated objects can be set while updating, for example:

const tag1 = tagRepository.findOne({
  filter: {
    id: 1
  },
});

await postRepository.update({
  filter: {
    id: 1
  },
  values: {
    title: "new post title",
    tags: [
      {
        id: tag1.id // Associate with tag1
      },
      {
        name: "tag2", // Create new tag and associate with it
      },
    ],
  },
});


await postRepository.update({
  filter: {
    id: 1
  },
  values: {
    tags: null // Disassociate post from tags
  },
})

Delete

Call the destroy() method in Repository to perform the deletion operation. Filtering condition has to be specified to delete.

await userRepository.destroy({
  filter: {
    status: "blocked",
  },
});

Constructor

It is usually not called directly by the developer, the instantiation is done mainly by specifying a coressponding repository type that is already registered in the parameter of db.colletion(). Repository type is registered through db.registerRepositories().

Signature

  • constructor(collection: Collection)

Example

import { Repository } from '@nocobase/database';

class MyRepository extends Repository {
  async myQuery(sql) {
    return this.database.sequelize.query(sql);
  }
}

db.registerRepositories({
  books: MyRepository
});

db.collection({
  name: 'books',
  // here link to the registered repository
  repository: 'books'
});

await db.sync();

const books = db.getRepository('books') as MyRepository;
await books.myQuery('SELECT * FROM books;');

Instance Member

database

上下文所在的数据库管理实例。

collection

对应的数据表管理实例。

model

对应的数据模型类。

实例方法

find()

从数据库查询数据集，可指定筛选条件、排序等。

Signature

  • async find(options?: FindOptions): Promise<Model[]>

类型

type Filter = FilterWithOperator | FilterWithValue | FilterAnd | FilterOr;
type Appends = string[];
type Except = string[];
type Fields = string[];
type Sort = string[] | string;

interface SequelizeFindOptions {
  limit?: number;
  offset?: number;
}

interface FilterByTk {
  filterByTk?: TargetKey;
}

interface CommonFindOptions extends Transactionable {
  filter?: Filter;
  fields?: Fields;
  appends?: Appends;
  except?: Except;
  sort?: Sort;
}

type FindOptions = SequelizeFindOptions & CommonFindOptions & FilterByTk;

详细信息

filter: Filter

查询条件，用于过滤数据结果。传入的查询参数中，key 为查询的字段名，value 可传要查询的值， 也可配合使用操作符进行其他条件的数据筛选。

// 查询 name 为 foo，并且 age 大于 18 的记录
repository.find({
  filter: {
    name: "foo",
    age: {
      $gt: 18,
    },
  }
})

更多操作符请参考 查询操作符。

filterByTk: TargetKey

通过 TargetKey 查询数据，为 filter 参数的便捷方法。TargetKey 具体是哪一个字段， 可在 Collection 中进行配置，默认为 primaryKey。


// 默认情况下，查找 id 为 1 的记录
repository.find({
  filterByTk: 1,
});

fields: string[]

查询列，用户控制数据字段结果。传入此参数之后，只会返回指定的字段。

except: string[]

排除列，用于控制数据字段结果。传入此参数之后，传入的字段将不会输出。

appends: string[]

追加列，用于加载关联数据。传入此参数之后，指定的关联字段将一并输出。

sort: string[] | string

指定查询结果排序方式，传入参数为字段名称，默认按照升序 asc 排序，若需按降序 desc 排序， 可在字段名称前加上 - 符号，如：['-id', 'name']，表示按 id desc, name asc 排序。

limit: number

限制结果数量，同 SQL 中的 limit

offset: number

查询偏移量，同 SQL 中的 offset

Example

const posts = db.getRepository('posts');

const results = await posts.find({
  filter: {
    createdAt: {
      $gt: '2022-01-01T00:00:00.000Z',
    }
  },
  fields: ['title'],
  appends: ['user'],
});

findOne()

从数据库查询特定条件的单条数据。相当于 Sequelize 中的 Model.findOne()。

Signature

  • async findOne(options?: FindOneOptions): Promise<Model | null>

Example

const posts = db.getRepository('posts');

const result = await posts.findOne({
  filterByTk: 1,
});

count()

从数据库查询特定条件的数据总数。相当于 Sequelize 中的 Model.count()。

Signature

  • count(options?: CountOptions): Promise<number>

类型

interface CountOptions extends Omit<SequelizeCountOptions, 'distinct' | 'where' | 'include'>, Transactionable {
  filter?: Filter;
}

Example

const books = db.getRepository('books');

const count = await books.count({
  filter: {
    title: '三字经'
  }
});

findAndCount()

从数据库查询特定条件的数据集和结果数。相当于 Sequelize 中的 Model.findAndCountAll()。

Signature

  • async findAndCount(options?: FindAndCountOptions): Promise<[Model[], number]>

类型

type FindAndCountOptions = Omit<SequelizeAndCountOptions, 'where' | 'include' | 'order'> & CommonFindOptions;

详细信息

查询参数与 find() 相同。返回值为一个数组，第一个元素为查询结果，第二个元素为结果总数。

create()

向数据表插入一条新创建的数据。相当于 Sequelize 中的 Model.create()。当要创建的数据对象携带关系字段的信息时，会一并创建或更新相应的关系数据记录。

Signature

  • async create<M extends Model>(options: CreateOptions): Promise<M>

Example

const posts = db.getRepository('posts');

const result = await posts.create({
  values: {
    title: 'NocoBase 1.0 发布日志',
    tags: [
      // 有关系表主键值时为更新该条数据
      { id: 1 },
      // 没有主键值时为创建新数据
      { name: 'NocoBase' },
    ]
  },
});

createMany()

向数据表插入多条新创建的数据。相当于多次调用 create() 方法。

Signature

  • createMany(options: CreateManyOptions): Promise<Model[]>

类型

interface CreateManyOptions extends BulkCreateOptions {
  records: Values[];
}

详细信息

  • records：要创建的记录的数据对象数组。
  • transaction: 事务对象。如果没有传入事务参数，该方法会自动创建一个内部事务。

Example

const posts = db.getRepository('posts');

const results = await posts.createMany({
  records: [
    {
      title: 'NocoBase 1.0 发布日志',
      tags: [
        // 有关系表主键值时为更新该条数据
        { id: 1 },
        // 没有主键值时为创建新数据
        { name: 'NocoBase' },
      ]
    },
    {
      title: 'NocoBase 1.1 发布日志',
      tags: [
        { id: 1 }
      ]
    },
  ],
});

update()

更新数据表中的数据。相当于 Sequelize 中的 Model.update()。当要更新的数据对象携带关系字段的信息时，会一并创建或更新相应的关系数据记录。

Signature

  • async update<M extends Model>(options: UpdateOptions): Promise<M>

Example

const posts = db.getRepository('posts');

const result = await posts.update({
  filterByTk: 1,
  values: {
    title: 'NocoBase 1.0 发布日志',
    tags: [
      // 有关系表主键值时为更新该条数据
      { id: 1 },
      // 没有主键值时为创建新数据
      { name: 'NocoBase' },
    ]
  },
});

destory()

删除数据表中的数据。相当于 Sequelize 中的 Model.destroy()。

Signature

  • async destory(options?: TargetKey | TargetKey[] | DestoryOptions): Promise<number>

类型

interface DestroyOptions extends SequelizeDestroyOptions {
  filter?: Filter;
  filterByTk?: TargetKey | TargetKey[];
  truncate?: boolean;
  context?: any;
}

详细信息

  • filter：指定要删除的记录的过滤条件。Filter 详细用法可参考 find() 方法。
  • filterByTk：按 TargetKey 指定要删除的记录的过滤条件。
  • truncate: 是否清空表数据，在没有传入 filter 或 filterByTk 参数时有效。
  • transaction: 事务对象。如果没有传入事务参数，该方法会自动创建一个内部事务。 image