MongoDB BulkWrite 更新操作 $set 不工作

Question

I am looping through products (variable records) with a bulkWrite updateOne operation on each product.

Once I update the records I can see the reservations array is being added to the document, totalQuantity is updated to the expected value (eg: if the totalQuantity is 2000 and the loadingTotal is 600 then the updated totalQuantity is 1400)

As you can see in line $set: { currentQuantity: "$totalQuantity" } I am trying to assign totalQuantity(1400) to currentQuantity. But this is not working.

for (const el of records) {
        promiseArray.push(
          Stock.bulkWrite(
            [
              {
                updateOne: {
                  filter: {
                    index: el.index,
                    product: el.product,
                    batchNo: el.batchNo,
                    agency,
                    totalQuantity: { $gte: el.loadingTotal },
                  },
                  update: {
                    $push: {
                      reservations: {
                        loadingSheetId: sheetAfterSave._id,
                        reservedCaseQuantity: el.loadingCaseCount,
                        reservedUnitQuantity: el.loadingUnitCount,
                        reservedTotalQuantity: el.loadingTotal,
                      },
                    },
                    $inc: { totalQuantity: -el.loadingTotal },
                    $set: { currentQuantity: "$totalQuantity" } // Issue
                  },
                },
              },
            ],
            { session: session }
          )
        );
      }

  const result = await Promise.all(promiseArray);
  console.log('******** Result Promise ********', result);

Any idea how I can get this solved??

ERROR MSG

[distribution] CastError: Cast to Number failed for value "$totalQuantity" at path "currentQuantity"
[distribution]     at SchemaNumber.cast (/app/node_modules/mongoose/lib/schema/number.js:384:11)
[distribution]     at SchemaNumber.SchemaType.applySetters (/app/node_modules/mongoose/lib/schematype.js:1031:12)
[distribution]     at SchemaNumber.SchemaType._castForQuery (/app/node_modules/mongoose/lib/schematype.js:1459:15)
[distribution]     at SchemaNumber.castForQuery (/app/node_modules/mongoose/lib/schema/number.js:436:14)
[distribution]     at SchemaNumber.SchemaType.castForQueryWrapper (/app/node_modules/mongoose/lib/schematype.js:1428:15)
[distribution]     at castUpdateVal (/app/node_modules/mongoose/lib/helpers/query/castUpdate.js:520:19)
[distribution]     at walkUpdatePath (/app/node_modules/mongoose/lib/helpers/query/castUpdate.js:347:22)
[distribution]     at castUpdate (/app/node_modules/mongoose/lib/helpers/query/castUpdate.js:94:7)
[distribution]     at /app/node_modules/mongoose/lib/helpers/model/castBulkWrite.js:70:37
[distribution]     at /app/node_modules/mongoose/lib/model.js:3502:35
[distribution]     at each (/app/node_modules/mongoose/lib/helpers/each.js:11:5)
[distribution]     at /app/node_modules/mongoose/lib/model.js:3502:5
[distribution]     at /app/node_modules/mongoose/lib/helpers/promiseOrCallback.js:31:5
[distribution]     at new Promise (<anonymous>)
[distribution]     at promiseOrCallback (/app/node_modules/mongoose/lib/helpers/promiseOrCallback.js:30:10)
[distribution]     at Function.Model.bulkWrite (/app/node_modules/mongoose/lib/model.js:3500:10) {
[distribution]   stringValue: '"$totalQuantity"',
[distribution]   messageFormat: undefined,
[distribution]   kind: 'Number',
[distribution]   value: '$totalQuantity',
[distribution]   path: 'currentQuantity',
[distribution]   reason: AssertionError [ERR_ASSERTION]: The expression evaluated to a falsy value:
[distribution]
[distribution]     assert.ok(!isNaN(val))
[distribution]
[distribution]       at castNumber (/app/node_modules/mongoose/lib/cast/number.js:28:10)
[distribution]       at SchemaNumber.cast (/app/node_modules/mongoose/lib/schema/number.js:382:12)
[distribution]       at SchemaNumber.SchemaType.applySetters (/app/node_modules/mongoose/lib/schematype.js:1031:12)
[distribution]       at SchemaNumber.SchemaType._castForQuery (/app/node_modules/mongoose/lib/schematype.js:1459:15)
[distribution]       at SchemaNumber.castForQuery (/app/node_modules/mongoose/lib/schema/number.js:436:14)
[distribution]       at SchemaNumber.SchemaType.castForQueryWrapper (/app/node_modules/mongoose/lib/schematype.js:1428:15)
[distribution]       at castUpdateVal (/app/node_modules/mongoose/lib/helpers/query/castUpdate.js:520:19)
[distribution]       at walkUpdatePath (/app/node_modules/mongoose/lib/helpers/query/castUpdate.js:347:22)
[distribution]       at castUpdate (/app/node_modules/mongoose/lib/helpers/query/castUpdate.js:94:7)
[distribution]       at /app/node_modules/mongoose/lib/helpers/model/castBulkWrite.js:70:37
[distribution]       at /app/node_modules/mongoose/lib/model.js:3502:35
[distribution]       at each (/app/node_modules/mongoose/lib/helpers/each.js:11:5)
[distribution]       at /app/node_modules/mongoose/lib/model.js:3502:5
[distribution]       at /app/node_modules/mongoose/lib/helpers/promiseOrCallback.js:31:5
[distribution]       at new Promise (<anonymous>)
[distribution]       at promiseOrCallback (/app/node_modules/mongoose/lib/helpers/promiseOrCallback.js:30:10) {
[distribution]     generatedMessage: true,
[distribution]     code: 'ERR_ASSERTION',
[distribution]     actual: false,
[distribution]     expected: true,
[distribution]     operator: '=='
[distribution]   }
[distribution] }

No luck.

below example from mongo official docs

{ "_id" : 1, "name" : "A", "hours" : 80, "resources" : 7 },
{ "_id" : 2, "name" : "B", "hours" : 40, "resources" : 4 }

db.planning.aggregate(
   [
     { $project: { name: 1, workdays: { $divide: [ "$hours", 8 ] } } }
   ]
)

{ "_id" : 1, "name" : "A", "workdays" : 10 }
{ "_id" : 2, "name" : "B", "workdays" : 5 }

using $hours to denote the dynamic values in the 2 documents. but in my case "$totalQuantity" doesnt work

https://docs.mongodb.com/manual/reference/operator/aggregation/divide/

Answer 1

The problem is that you are trying to store the text of "$totalQuantity" instead of a numeric value in this line:

$set: { currentQuantity: "$totalQuantity" }

Instead of that, a hardcoded numeric value of

$set: { currentQuantity: 5 }

would set the value to 5. Now, you need to find out what the dynamic value is. If you have a $totalQuantity variable that has a number as value, then you can do something like this:

$set: { currentQuantity: $totalQuantity }

If not, then you will need to figure out how you can access the value that you need and use that knowledge to access it.

Answer 2

By Prasad_Saya

Hi @Shanka_Somasiri, I am not sure about what you are trying. Here is how you do the update using Aggregation Pipeline, for example.

I have an input document:

{
   _id: 1,
   reservations: [ ]
}

Here is a document I want to push into the reservations array.

var docToUpdate = { loadingShetId: 12, reservedCaseQty: 200 }

The update query:

db.test.updateOne(
  { _id: 1 },
  [
    {
         $set: {
             reservations: {
                 $concatArrays: [ "$reservations", [ docToUpdate ] ]
             }
         }
    }
  ]
)

The updated document:

{
        "_id" : 1,
        "reservations" : [
                {
                        "loadingShetId" : 12,
                        "reservedCaseQty" : 200
                }
        ]
}

The remaining field updates:

$inc: { totalQuantity: -el.loadingTotal }
$set: { currentQuantity: "$totalQuantity" }

Can be coded as follows:

totalQuantity: { $add: [ "$totalQuantity", -el.loadingTotal ] }
currentQuantity: "$totalQuantity"

So, the update query will become:

db.test.updateOne(
  { _id: 1 },
  [
    {
         $set: {
             reservations: {
                 $concatArrays: [ "$reservations", [ docToUpdate ] ]
             },
             totalQuantity: { $add: [ "$totalQuantity", -el.loadingTotal ] },
             currentQuantity: "$totalQuantity"
         }
    }
  ]
)