ali-rds

Aliyun RDS client. Sub module of ali-sdk.

RDS Usage

RDS, Relational Database Service. Equal to well know Amazon RDS. Support MySQL, SQL Server and PostgreSQL.

MySQL Usage

Create RDS instance

const rds = require('ali-rds');

const db = rds({
  host: 'your-rds-address.mysql.rds.aliyuncs.com',
  port: 3306,
  user: 'your-username',
  password: 'your-password',
  database: 'your-database-name',

  // optional params
  // The charset for the connection.
  // This is called "collation" in the SQL-level of MySQL (like utf8_general_ci).
  // If a SQL-level charset is specified (like utf8mb4)
  // then the default collation for that charset is used. (Default: 'UTF8_GENERAL_CI')
  // charset: 'utf8_general_ci',
  //
  // The maximum number of connections to create at once. (Default: 10)
  // connectionLimit: 10,
  //
  // The maximum number of connection requests the pool will queue
  // before returning an error from getConnection.
  // If set to 0, there is no limit to the number of queued connection requests. (Default: 0)
  // queueLimit: 0,
});

Insert

• Insert one row

let row = {
  name: 'fengmk2',
  otherField: 'other field value',
  createdAt: db.literals.now, // `now()` on db server
  // ...
};
let result = yield db.insert('table-name', row);
console.log(result);
{ fieldCount: 0,
  affectedRows: 1,
  insertId: 3710,
  serverStatus: 2,
  warningCount: 2,
  message: '',
  protocol41: true,
  changedRows: 0 }

• Insert multi rows

Will execute under a transaction and auto commit.

let rows = [
  {
    name: 'fengmk1',
    otherField: 'other field value',
    createdAt: db.literals.now, // `now()` on db server
    // ...
  },
  {
    name: 'fengmk2',
    otherField: 'other field value',
    createdAt: db.literals.now, // `now()` on db server
    // ...
  },
  // ...
];

let results = yield db.insert('table-name', rows);
console.log(result);
{ fieldCount: 0,
  affectedRows: 2,
  insertId: 3840,
  serverStatus: 2,
  warningCount: 2,
  message: '&Records: 2  Duplicates: 0  Warnings: 0',
  protocol41: true,
  changedRows: 0 }

Update

• Update a row with primary key: id

let row = {
  id: 123,
  name: 'fengmk2',
  otherField: 'other field value',
  modifiedAt: db.literals.now, // `now()` on db server
};
let result = yield db.update('table-name', row);
console.log(result);
{ fieldCount: 0,
  affectedRows: 1,
  insertId: 0,
  serverStatus: 2,
  warningCount: 0,
  message: '(Rows matched: 1  Changed: 1  Warnings: 0',
  protocol41: true,
  changedRows: 1 }

• Update a row with options.where and options.columns

let row = {
  name: 'fengmk2',
  otherField: 'other field value',
  modifiedAt: db.literals.now, // `now()` on db server
};
let result = yield db.update('table-name', row, {
  where: { name: row.name },
  columns: [ 'otherField', 'modifiedAt' ]
});
console.log(result);
{ fieldCount: 0,
  affectedRows: 1,
  insertId: 0,
  serverStatus: 2,
  warningCount: 0,
  message: '(Rows matched: 1  Changed: 1  Warnings: 0',
  protocol41: true,
  changedRows: 1 }

Get

• Get a row

let row = yield db.get('table-name', { name: 'fengmk2' });

=> SELECT * FROM `table-name` WHERE `name` = 'fengmk2'

Select

• Select all rows

let rows = yield db.select('table-name');

=> SELECT * FROM `table-name`

• Select rows with condition

let rows = yield db.select('table-name', {
  where: {
    type: 'javascript'
  },
  columns: ['author', 'title'],
  orders: [['id', 'desc']]
});

=> SELECT `author`, `title` FROM `table-name`
 WHERE `type` = 'javascript' ORDER BY `id` DESC

Delete

• Delete with condition

let result = yield db.delete('table-name', {
  name: 'fengmk2'
});

=> DELETE FROM `table-name` WHERE `name` = 'fengmk2'

Count

• Get count from a table with condition

let count = yield db.count('table-name', {
  type: 'javascript'
});

=> SELECT COUNT(*) AS count FROM `table-name` WHERE `type` = 'javascript';

Transactions

beginTransaction, commit or rollback

let tran = yield db.beginTransaction();

try {
  yield tran.insert(table, row1);
  yield tran.update(table, row2);
  yield tran.commit();
} catch (err) {
  // error, rollback
  yield tran.rollback(); // rollback call won't throw err
  throw err;
}

Transaction with scope

API: *beginTransactionScope(scope)

All query run in scope will under a same transaction. We will auto commit or rollback for you.

var result = yield db.beginTransactionScope(function* (conn) {
  // don't commit or rollback by yourself
  yield conn.insert(table, row1);
  yield conn.update(table, row2);
  return { success: true };
});
// if error throw on scope, will auto rollback

Transaction on koa

API: *beginTransactionScope(scope, ctx)

Use koa's context to make sure only one active transaction on one ctx.

function* foo(ctx, data1) {
  return yield db.beginTransactionScope(function* (conn) {
    yield conn.insert(table1, data1);
    return { success: true };
  }, ctx);
}

function* bar(ctx, data2) {
  return yield db.beginTransactionScope(function* (conn) {
    // execute foo with the same transaction scope
    yield foo(ctx, { foo: 'bar' });
    yield conn.insert(table2, data2);
    return { success: true };
  }, ctx);
}

Raw Queries

• Query with arguments

let rows = yield db.query('SELECT * FROM your_table LIMIT 100');
console.log(rows);

• Query with arguments

let rows = yield db.query('SELECT * FROM your_table WHERE id=?', [123]);
console.log(rows);

SQL Server Usage

TBD

---

APIs

• * Meaning this function is yieldable.

IO queries

• *query(sql[, values)
• *queryOne(sql[, values)
• *select(table, options)
• *get(table, where, options)
• *insert(table, row[s], options)
• *update(table, row, options)
• *delete(table, where)
• *count(table, where)

Transactions

• *beginTransaction()
• *beginTransactionScope(scope)

Utils

• escape(value, stringifyObjects, timeZone)
• escapeId(value, forbidQualified)
• format(sql, values, stringifyObjects, timeZone)

Literals

yield db.insert('user', {
  name: 'fengmk2',
  createdAt: db.literals.now,
});

=>

INSERT INTO `user` SET `name` = 'fengmk2', `createdAt` = now()

Custom Literal

let session = new db.literals.Literal('session()');

TODO

• MySQL
  • Pool
  • Cluster
• SQL Server
• PostgreSQL

License

MIT