The DashDB connector enables LoopBack applications to connect to DashDB data sources.
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loopback-connector-dashdb

IBM® DashDB® is the database of choice for robust, enterprise-wide solutions handling high-volume workloads. It is optimized to deliver industry-leading performance while lowering costs. The loopback-connector-dashdb module is the LoopBack connector for dashDB.

The LoopBack DashDB connector supports:

  • All CRUD operations.
  • Queries with fields, limit, order, skip and where filters.
  • All supported DASHDB LUW versions as well as dashDB. Note for dashDB set supportDashDB in the loopback datasource definition. Column organized tables are not supported.

Installation

Enter the following in the top-level directory of your LoopBack application:

$ npm install loopback-connector-dashdb --save

The --save option adds the dependency to the application’s package.json file.

Configuration

Use the data source generator (lb datasource) to add the DASHDB data source to your application. The entry in the application’s server/datasources.json will look something like this:

"mydb": {
  "name": "mydb",
  "connector": "dashdb"
}

Edit server/datasources.json to add other supported properties as required:

"mydb": {
  "name": "mydb",
  "connector": "dashdb",
  "username": <username>,
  "password": <password>,
  "database": <database name>,
  "hostname": <dashdb server hostname>,
  "port":     <port number>
}

The following table describes the connector properties.

Property Type Description
database String Database name
schema String Specifies the default schema name that is used to qualify unqualified database objects in dynamically prepared SQL statements. The value of this property sets the value in the CURRENT SCHEMA special register on the database server. The schema name is case-sensitive, and must be specified in uppercase characters
username String DASHDB Username
password String DASHDB password associated with the username above
hostname String DASHDB server hostname or IP address
port String DASHDB server TCP port number
useLimitOffset Boolean LIMIT and OFFSET must be configured on the DASHDB server before use (compatibility mode)
supportDashDB Boolean Create ROW ORGANIZED tables to support dashDB.

Alternatively, you can create and configure the data source in JavaScript code. For example:

var DataSource = require('loopback-datasource-juggler').DataSource;
var DASHDB = require('loopback-connector-dashdb');

var config = {
  username: process.env.DASHDB_USERNAME,
  password: process.env.DASHDB_PASSWORD,
  hostname: process.env.DASHDB_HOSTNAME,
  port: 50000,
  database: 'SQLDB',
};

var db = new DataSource(DASHDB, config);

var User = db.define('User', {
  name: { type: String },
  email: { type: String },
});

db.autoupdate('User', function(err) {
  if (err) {
    console.log(err);
    return;
  }

  User.create({
    name: 'Tony',
    email: [email protected]',
  }, function(err, user) {
    console.log(err, user);
  });

  User.find({ where: { name: 'Tony' }}, function(err, users) {
    console.log(err, users);
  });

  User.destroyAll(function() {
    console.log('example complete');
  });
});

Operators

Here is a list of operators supported by the connector:

  • regexp operator
    Employee.find({where: {taskCode: {regexp: /tsk/i}}}, function(err, result) {
      if (err) throw err;
      console.log('Found instance with regexp: ' + JSON.stringify(result));
    });
    
  • like operator
    Employee.find({where: {taskCode: {like: 'TSK%'}}}, function(err, result) {
      if (err) throw err;
      console.log('Found instance with like: ' + JSON.stringify(result));
    });
    
  • nlike operator
    Employee.find({where: {taskCode: {nlike: 'TSK%'}}}, function(err, result) {
      if (err) throw err;
      console.log('Found instance with like: ' + JSON.stringify(result));
    });
    

Running tests

Own instance

If you have a local or remote DashDB instance and would like to use that to run the test suite, use the following command:

  • Linux
    DASHDB_HOSTNAME=<HOST> DASHDB_PORTNUM=<PORT> DASHDB_USERNAME=<USER> DASHDB_PASSWORD=<PASSWORD> DASHDB_DATABASE=<DATABASE> DASHDB_SCHEMA=<SCHEMA> CI=true npm test
    
  • Windows
    SET DASHDB_HOSTNAME=<HOST>
    SET DASHDB_PORTNUM=<PORT>
    SET DASHDB_USERNAME=<USER>
    SET DASHDB_PASSWORD=<PASSWORD>
    SET DASHDB_DATABASE=<DATABASE>
    SET DASHDB_SCHEMA=<SCHEMA>
    SET CI=true
    npm test
    

Docker

  • DashDB has a docker image which could be signed up for a trial version and be used for testing. For more information, please visit: DashDB Docker
  • Once the instance is ready, please follow the above information on how to run tests using your own instance