MongoDB converts number to string in scientific notation

问题

I want to get full number as a String, but instead "1490650000000" it returns scientific notation "1.49065e+12"

Here's how I try to convert it:

{$substr: ["$myNumber", 0, -1]};

Any ideas how to prevent it?

Note: I'm using v3.6 and can't upgrade to use $toString (thanks mlab).

回答1:

If you have mongodb 4.0 then you can use $toLong aggregation

db.collection.aggregate([
  {
    "$project": {
      "myNumber": {
        "$toLong": "$myNumber"
      }
    }
  }
])

回答2:

You can try as below.

db.collectionName.aggregate([
{ $addFields: { "strFld": {$toString: {$toLong:"$numberFiled"}}} },
])

来源：https://stackoverflow.com/questions/51230909/mongodb-converts-number-to-string-in-scientific-notation