mark一下
参考:
https://blog.csdn.net/laoyang360/article/details/72594344

1.str转long当int很长时db.teststatement.find({"ctime":{$type: 2}}).forEach( function (x) {
x.ctime= NumberLong (x.ctime);
db.teststatement.save(x);
})
2.int转strdb.redefine_share_backwards.find( { 'share_uid' : { $gte : 0 } } ).forEach( function (x) {x.share_uid = ""+x.share_uid;db.redefine_share_backwards.save(x);})