Script to do a one time update to a database

first.js

var config  = require(''); // Config file containing DB credentials
var mysql   = require('mysql');
var Promise = require('bluebird');

Promise.promisifyAll(require("mysql/lib/Connection").prototype);
Promise.promisifyAll(require("mysql/lib/Pool").prototype);

var pool = mysql.createPool(config.dbConfig);



pool.on('error', function(err) {
	console.log('Database Error %s', err)
});


pool.on('enqueue', function () {
  console.log('Database connection pool queued.');
});	



function getClients() {

	return pool.getConnectionAsync() 
	.then(function(connection) {
		return connection.queryAsync('select * from your_table;')
		.spread(function(rows, columns) {
			connection.release();
			return rows;
		});
	});
};


function ErrDupField(e) {
	return (e.cause.errno === 1060);
}



function addClientIdField(table) {
	console.log(table);

	return pool.getConnectionAsync()
	.then(function(connection) {
		return connection.queryAsync('ALTER TABLE '+table.name+' ADD clientID VARCHAR(50) NOT NULL;').then(function() {
			return connection.release();
		}).catch(ErrDupField, function(e) {
			console.log('%s already has clientID', table.name);
		});
	});
};


function addClientID(client, table) {
	return pool.getConnectionAsync()
	.then(function(connection) {
		return connection.queryAsync('Update '+table.name+' SET clientID = "'+client.id+'" WHERE '+table.accountField+' = "'+client[table.clientField]+'";')
		.then(function() {
			return connection.release();
		});
	});
};


getClients()
.then(function(clients) {
	var tables = [
		{
			"name": "", // name of the table to update
			"accountField": "", // table field to update
			"clientField": "" // Field of another table to update data from  
		}
	];

	Promise.map(tables, function(table) {
		return addClientIdField(table).return(table);
	})
	.each(function(table) {
		return Promise.map(clients, function(client) {
			return addClientID(client, table).return(client.name);
		}, {concurrency: 5})
		.tap(console.log);
	})
	.finally(function() {
		console.log('All Clients Udpated');
		process.exit(0);
	});

});