-- 交友 -- srd_user_friend create table srd_user_friend ( id bigint unsigned auto_increment comment '主键' primary key, user_id bigint unsigned not null comment '用户主键', friend_id bigint unsigned not null comment '好友', state tinyint(1) default 0 not null comment '对方是否同意', created_at timestamp default CURRENT_TIMESTAMP not null comment '创建时间', updated_at timestamp null comment '修改时间', constraint srd_user_friend_srd_user_id_fk foreign key (user_id) references srd_user (id) on delete cascade, constraint srd_user_friend_srd_user_id_fk_2 foreign key (friend_id) references srd_user (id) on delete cascade ) comment '交友';