CODEWITHSUNDEEP
mongodb
NGabioud
NGabioud

Reputation: 375

How do I discard a record that throws an error?

I have a MongoDB query and I want the query to continue after one error and skip that record.

I get the following error:

Error: getMore command failed: { "operationTime" : Timestamp(1547144095, 335), "ok" : 0, "errmsg" : "Failed to parse objectId '' in $convert with no onError value: >Invalid string length for parsing to OID, expected 24 but found 0", "code" : 241, "codeName" : "ConversionFailure", "$clusterTime" : { "clusterTime" : Timestamp(1547144095, 335), "signature" : { "hash" : BinData(0,"aMqO7W+xnEbbUw6UsX/cxr2jxzo="), "keyId" : NumberLong("6626865028530176001") } } }

I don't want to fix the error, I just want to ignore it and want the query to continue. Is there a way to do that?

Upvotes: 0

Views: 3678

Answers (1)

Stennie
Stennie

Reputation: 65393

Assuming test data like:

 db.things.insert([{ myfield: ObjectId()}, { myfield:  "Some text"}])

You can avoid passing invalid field values by matching against the expected $type of the value you are converting:

db.things.aggregate([
    { $match: {
        myfield: { $type: "objectId" }
    }},
    { $addFields: {
        converted: {
            $convert: { 
                input: "$myfield",
                to: "objectId",
            }
        }
    }},
])

Alternatively, you could set the onError value in $convert to something you can use in your aggregation pipeline (for example, with a $match or $cond expression):

db.things.aggregate([
    { $addFields: {
        converted: {
            $convert: { 
                input: "$myfield",
                to: "objectId",
                onError: 0
            }
        }
    }},
    { $match: {
        converted: { $ne: 0 }
    }}
])

Upvotes: 5

Related Questions