larvitdbmigration

Database migration tool

This is used to keep track of the database structure, and update it when need be via deploys.

At the moment only MariaDB(/MySQL) is supported.

A table by default called db_version will be created, containing a single integer.

Scripts will be placed by default in /dbmigration/.js

Each migration script will be ran, and the db_version increased, until no more migration scripts exists.

Usage

Application startup script

In your application startup script, do something like this:

'use strict';

var dbMigration = require('larvitdbmigration');

dbMigration({'host': '127.0.0.1', 'user': 'bar', 'database': 'bar'})(function(err) {
	if (err)
		throw err;

	// Now database is migrated and ready for use!
});

To use custom table name and/or script path, just change

	dbMigration({'host': '127.0.0.1', 'user': 'bar', 'database': 'bar'})(function(err) {

to

	dbMigration({'host': '127.0.0.1', 'user': 'bar', 'database': 'bar', 'tableName': 'some_table', 'migrationScriptsPath': './scripts_yo'})(function(err) {

Example migration script

Lets say the current database have a table like this:

CREATE TABLE bloj (nisse int(11));

And in the next deploy we'd like to change the column name "nisse" to "hasse". Then create the file /dbmigration/1.js with this content:

'use strict';

var db = require('db');

exports = module.exports = function(cb) {
	db.query('ALTER TABLE bloj CHANGE nisse hasse int(11);', cb);
}

Tadaaa! Now this gets done once and the version will be bumped to 1. If you then create a script named "2.js" you might guess what happends. :)