CREATE TABLE "activity_stream" (
    `asid` serial not null,
    `actor` int not null,
    `targetUser` int not null,
    `event` varchar (50) not null,
    `elementType` varchar (50) not null,
    `elementID` int not null,
    `createdAt` timestamp not null,
    `extra` varchar (200) DEFAULT '' not null,
    primary key(`asid`)
);