alasql/test/test038.js

AlaSQL.js - JavaScript SQL database library for relational and graph data manipulation with support of localStorage, IndexedDB, and Excel

if(typeof exports === 'object') {
	var assert = require("assert");
	var alasql = require('..');
};

describe('Test 38', function() {
	describe('LEFT AND RIGHT JOINS', function(){

		var db;
		it('Prepare database', function(done){
			db = new alasql.Database("db");

			db.exec('CREATE TABLE one (a INT, b INT)');
			db.exec('INSERT INTO one VALUES (1,10),(2,20),(3,30), (4,40)');

			db.exec('CREATE TABLE two (e INT, f INT)');
			db.exec('INSERT INTO two VALUES (1,100),(2,200),(3,300), (1000,1000), (2000,2000)');

			db.exec('CREATE TABLE three (g INT, h INT)');
			db.exec('INSERT INTO three VALUES (200,2000), (1000,10000),(2000,20000), (3000,30000)');
			done();
		});

		it('1x LEFT JOIN', function(done){
			var res = db.exec("SELECT * FROM one LEFT JOIN two ON one.a = two.e");
			assert.equal(res.length,4);
			done();
		});

		it('1x RIGHT JOIN', function(done){
			var res = db.exec("SELECT * FROM two RIGHT JOIN one ON one.a = two.e");
			assert.equal(res.length,4);
			done();
		});

		it('2x LEFT JOIN', function(done){
			var res = db.exec("SELECT * FROM one "+
				" LEFT JOIN two ON one.a = two.e"+
				" LEFT JOIN three ON two.f = three.g" );
			assert.equal(res.length,4);
			done();
		});
/*
		it('2x RIGHT JOIN', function(done){
			var res = db.exec("SELECT * FROM three "+
				" RIGHT JOIN two ON two.f = three.g"+
				" RIGHT JOIN one ON one.a = two.e" );
			console.table(res);
			assert.equal(res.length,4);
			done();
		});
*/
/*
		it('2x RIGHT JOIN', function(done){
			var res = db.exec("SELECT * FROM one "+
				" OUTER JOIN two ON one.a = two.e "+
				" OUTER JOIN three ON two.f = three.g " );
			console.table(res);
			assert.equal(res.length,2);
			done();
		});
*/
		it('2x INNER JOIN', function(done){
			var res = db.exec("SELECT * FROM one "+
				" JOIN two ON one.a = two.e"+
				" JOIN three ON two.f = three.g" );
			assert.equal(res.length,1);
			done();
		});

		it('2x INNER JOIN', function(done){
			var res = db.exec("SELECT * FROM three "+
				" INNER JOIN two ON three.g = two.f"+ 
				" INNER JOIN one ON two.e = one.a");
			assert.equal(res.length,1);
			done();
		});

	});
});