The source code

    Ext.data.GearsDB = Ext.extend(Ext.data.SqlDB, {
    	// abstract methods
        open : function(db, cb, scope){
            this.conn = google.gears.factory.create('beta.database', '1.0');
            this.conn.open(db);
            this.openState = true;
    		Ext.callback(cb, scope, [this]);
    		this.fireEvent('open', this);
        },

    	close : function(){
            this.conn.close();
            this.fireEvent('close', this);
        },

        exec : function(sql, cb, scope){
            this.conn.execute(sql).close();
            Ext.callback(cb, scope, [true]);
        },

    	execBy : function(sql, args, cb, scope){
    	    this.conn.execute(sql, args).close();
            Ext.callback(cb, scope, [true]);
        },

    	query : function(sql, cb, scope){
            var rs = this.conn.execute(sql);
            var r = this.readResults(rs);
            Ext.callback(cb, scope, [r]);
            return r;
        },

    	queryBy : function(sql, args, cb, scope){
            var rs = this.conn.execute(sql, args);
            var r = this.readResults(rs);
            Ext.callback(cb, scope, [r]);
            return r;
        },

        readResults : function(rs){
            var r = [];
            if(rs){
                var c = rs.fieldCount();
                // precache field names
                var fs = [];
                for(var i = 0; i < c; i++){
                    fs[i] = rs.fieldName(i);
                }
                // read the data
                while(rs.isValidRow()){
                    var o = {};
                    for(var i = 0; i < c; i++){
                        o[fs[i]] = rs.field(i);
                    }
                    r[r.length] = o;
                    rs.next();
                }
                rs.close();
            }
            return r;
        },

        // protected/inherited method
        isOpen : function(){
    		return this.openState;
    	},

    	getTable : function(name, keyName){
    		return new Ext.data.SqlDB.Table(this, name, keyName);
    	}
    });