$ mongo test
MongoDB shell version: 3.2.10
connecting to: test
>
> db.test.insertOne({ x: 0.1 })
{
    "acknowledged" : true,
    "insertedId" : ObjectId("588a3f711554cc7d70642fa1")
}
> db.test.updateOne({}, { $inc: { x: 0.2 } })
{ "acknowledged" : true, "matchedCount" : 1, "modifiedCount" : 1 }
> db.test.findOne()
{ "_id" : ObjectId("588a3f711554cc7d70642fa1"), "x" : 0.30000000000000004 }
>

$ node
> 0.1
0.1
> 0.2
0.2
> 0.1 * 0.2
0.020000000000000004
> 0.1 * 0.1
0.010000000000000002
>

https://thecodebarbarian.com/a-nodejs-perspective-on-mongodb-34-decimal.html

http://adripofjavascript.com/blog/drips/avoiding-problems-with-decimal-math-in-javascript.html

IEEE 764

@waitingsong 你们是怎么解决呢？

@yhj8899 我这边数据库都是存的整数，用的时候除以100

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