alasql/src/93sqlite.js

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

//
// 91websql.js
// WebSQL database support
// (c) 2014, Andrey Gershun
//

var SQLITE = alasql.engines.SQLITE = function (){};

SQLITE.createDatabase = function(wdbid, args, ifnotexists, dbid, cb){
	throw new Error('Connot create SQLITE database in memory. Attach it.');
};

SQLITE.dropDatabase = function(databaseid){
	throw new Error('This is impossible to drop SQLite database. Detach it.');
};

SQLITE.attachDatabase = function(sqldbid, dbid, args, params, cb){
	var res = 1;
	if(alasql.databases[dbid]) {
		throw new Error('Unable to attach database as "'+dbid+'" because it already exists');
	};


	if(args[0] && (args[0] instanceof yy.StringValue)
		|| (args[0] instanceof yy.ParamValue)) {

		if(args[0] instanceof yy.StringValue) {
			var value = args[0].value;
		} else if(args[0] instanceof yy.ParamValue) {
			var value = params[args[0].param];
		}
		alasql.utils.loadBinaryFile(value,true,function(data){
			var db = new alasql.Database(dbid || sqldbid);
			db.engineid = "SQLITE";
			db.sqldbid = sqldbid;
			var sqldb = db.sqldb = new SQL.Database(data);
			db.tables = [];
			var tables = sqldb.exec("SELECT * FROM sqlite_master WHERE type='table'")[0].values;

		   	tables.forEach(function(tbl){
		   		db.tables[tbl[1]] = {};
		   		var columns = db.tables[tbl[1]].columns = [];
		   		var ast = alasql.parse(tbl[4]);
//		   		console.log(ast);
		   		var coldefs = ast.statements[0].columns;
		   		if(coldefs && coldefs.length>0) {
		   			coldefs.forEach(function(cd){
			   			columns.push(cd);
		   			});
		   		}

		   	});
//		   	console.log(35,db.tables);

		   	cb(1);
		}, function(err){
			throw new Error('Cannot open SQLite database file "'+args[0].value+'"');
		})
		return res;
	} else {
		throw new Error('Cannot attach SQLite database without a file');
	};

	return res;
}

SQLITE.fromTable = function(databaseid, tableid, cb, idx, query){
	var data = alasql.databases[databaseid].sqldb.exec("SELECT * FROM "+tableid);
	var columns = query.sources[idx].columns = [];
	if(data[0].columns.length > 0) {
		data[0].columns.forEach(function(columnid) {
			columns.push({columnid:columnid});
		});
	};

	var res = [];
	if(data[0].values.length > 0) {
		data[0].values.forEach(function(d){
			var r = {};
			columns.forEach(function(col,idx){
				r[col.columnid] = d[idx];
			});
			res.push(r);
		});
	}
	if(cb) cb(res, idx, query);
};

SQLITE.intoTable = function(databaseid, tableid, value, columns, cb) {
	var sqldb = alasql.databases[databaseid].sqldb;
	for(var i=0, ilen = value.length;i<ilen;i++) {
		var s = "INSERT INTO "+tableid+" (";
		var d = value[i];
		var keys = Object.keys(d);
		s += keys.join(",");
		s += ") VALUES (";
		s += keys.map(function(k){
			v = d[k];
			if(typeof v == 'string') v = "'"+v+"'";
			return v;
		}).join(",");
		s += ")";
		sqldb.exec(s);
	};
	var res = ilen;
	if(cb) cb(res);
	return res;
};