Class DataAdapterBaseAbstract

Gets the underlying context.

Counts a list of items.

Example

import { IDataRepository } from '@egomobile/orm'

class User {
  id: number = -1;
}

async function countActiveUsers(repo: IDataRepository): Promise<number> {
  // in SQL context
  return await repo.count(User, {
    where: 'is_active=$1 AND (is_deleted=$2 OR is_deleted IS NULL)',
    params: [ true, false ],  // $1, $2
  })
}
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Finds a list of items.

Example

import { IDataRepository } from '@egomobile/orm'

// keep sure to initialize your props
// with a value, which is not (undefined)
class User {
  id: number = -1;
  first_name: string = '';
  last_name: string = '';
  is_active: boolean | null = null;
  is_deleted: boolean = false;
}

async function load10ActiveUsersAndSkipFirst(repo: IDataRepository): Promise<User[]> {
  // in SQL context
  return await repo.find(User, {
    where: 'is_active=$1 AND (is_deleted=$2 OR is_deleted IS NULL)',
    params: [ true, false ],  // $1, $2

    offset: 1,
    limit: 10
  })
}
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Tries to find a simple item.

Example

import { IDataRepository } from '@egomobile/orm'

// keep sure to initialize your props
// with a value, which is not (undefined)
class User {
  id: number = -1;
  first_name: string = '';
  last_name: string = '';
  is_active: boolean | null = null;
  is_deleted: boolean = false;
}

async function loadLastActiveUser(repo: IDataRepository): Promise<User> {
  // in SQL context
  return await repo.findOne(User, {
    where: 'is_active=$1 AND (is_deleted=$2 OR is_deleted IS NULL)',
    params: [ true, false ],  // $1, $2

    sort: {
      'created': 'DESC',  // first sort by 'created' (descending)
      'id': 'DESC',  // then by 'id' (descending)
      'last_name': 'ASC',  // then by 'last_name' (ascending)
      'first_name': 'ASC'  // then by 'first_name' (ascending)
    }
  })
}
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Returns an entity by its type.

Returns an entity by its type or throws an exception if not found.

Returns the list of entity/table fields, which represent the IDs of a row.

Returns the list of entity fields columns, which represent the IDs of a row, or throws an exception if not defined.

Returns the name of the underlying entity/table by type or throws an exception, if not configured.

Insert one or more entities.

Example

import { IDataRepository } from '@egomobile/orm'

// keep sure to initialize your props
// with a value, which is not (undefined)
class User {
  id: number | null = null;
  first_name: string = '';
  last_name: string = '';
  is_active: boolean | null = null;
  is_deleted: boolean = false;
}

async function createUser(repo: IDataRepository, firstName: string, lastName: string): Promise<User> {
  const newUser = new User()
  newUser.last_name = lastName
  newUser.first_name = firstName
  newUser.is_active = true

  await repo.insert(newUser)
}
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Does a raw query.

Example

import { IDataRepository } from '@egomobile/orm'

async function deleteInactiveUsers(repo: IDataRepository) {
  // in SQL context
  //
  // result is an object or value
  // from the underlying data adapter itself
  const result: any = await repo.query(
    "UPDATE users SET is_deleted=$1 WHERE is_active=$2;",
    false, false  // $1, $2
  )
}
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Does a raw query and maps the result(s) to entity objects. The classes do not need to be configured in context, so it is possbile to implement and work with "joins". The difference to queryAndMap() is, that is makes use of cursor pattern instead of returning final data.

Example

import { IDataRepository } from '@egomobile/orm'

class UserAndRole {
  role_id!: string;
  user_id!: string;
}

async function loadUserRoles(repo: IDataRepository): AsyncGenerator<UserAndRole> {
  // PostgreSQL example
  // s. https://github.com/egomobile/node-orm-pg

  return repo.queryAndIterate(
    UserAndRole,  // type of the target entity
                  // does not need to be configured
                  // in data context

    // build query
    "SELECT DISTINCT ur.id AS role_id, u.id AS user_id " +
    "FROM user_roles ur " +
    "INNER JOIN users u ON u.id = ur.user_id " +
    "WHERE u.is_active = $1 AND u.is_deleted = $2;",

    // additional parameters
    true, false  // $1, $2
  )
}

const iterator = loadUserRoles(
  // ... your repo instance ...
)

for await (const userAndRole of iterator) {
  // your code ...
}
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Does a raw query and maps the result(s) to entity objects. The classes do not need to be configured in context, so it is possbile to implement and work with "joins".

Example

import { IDataRepository } from '@egomobile/orm'

class UserAndRole {
  role_id!: string;
  user_id!: string;
}

async function loadUserRoles(repo: IDataRepository): Promise<UserAndRole[]> {
  // PostgreSQL example
  // s. https://github.com/egomobile/node-orm-pg

  return await repo.queryAndMap(
    UserAndRole,  // type of the target entity
                  // does not need to be configured
                  // in data context

    // build query
    "SELECT DISTINCT ur.id AS role_id, u.id AS user_id " +
    "FROM user_roles ur " +
    "INNER JOIN users u ON u.id = ur.user_id " +
    "WHERE u.is_active = $1 AND u.is_deleted = $2;",

    // additional parameters
    true, false  // $1, $2
  )
}
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Removes one or more entities.

Example

import { IDataRepository } from '@egomobile/orm'

// keep sure to initialize your props
// with a value, which is not (undefined)
class User {
  id: number = -1;
  is_active: boolean | null = null;
}

async function removeInactiveUsers(repo: IDataRepository, users: User[]) {
  const inactiveUsers = users.find(u => u.is_active === false)

  await repo.remove(inactiveUsers)
}
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Sets the data context.

Updates one or more entities.

Example

import { IDataRepository } from '@egomobile/orm'

// keep sure to initialize your props
// with a value, which is not (undefined)
class User {
  id: number = -1;
  is_deleted: boolean = false;
}

async function deleteUsers(repo: IDataRepository, users: User[]) {
  users.forEach((user) => {
    user.is_deleted = true
  })

  await repo.update(inactiveUsers)
}
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