const _ = db.command
                db.collection('comment')
                .doc(postId)
                .set({
                    data: {
                        postId: postId,
                        comments: _.push(comment),
                        updateTime: new Date().getTime(),
                        teamMem: teamMem
                    }
                }).then(res => {
                }).catch(err => {
                })

comments怎么没有