DocDB Elastic cannot use regex filter that starts with escape characters

Hello AWS Customer

From the details provided , kindly allow me to mention it seems in both cases you have provided similar query. Based on the testing in my environment, I can see that query is working and not providing any error.

Testing Details :

Created collection :

rs0:PRIMARY> db.createCollection("mycoll")
{ "ok" : 1, "operationTime" : Timestamp(1698782387, 1) }

Inserted data :

rs0:PRIMARY> db.mycoll.insert({"name":"anushka", "age":54, "Test" : { "Date" : "2023-06-04T02:52:25.638-07:00", "Status" : "Completed" }});
WriteResult({ "nInserted" : 1 })
rs0:PRIMARY> db.mycoll.insert({"name":"joe", "age":45, "Test" : { "Date" : "2023-05-04T02:52:25.638-07:00", "Status" : "Pending" }});
WriteResult({ "nInserted" : 1 })

Find query :

rs0:PRIMARY> db.mycoll.findOne({"name":"joe"});
{
        "_id" : ObjectId("65415cb455a04e2c7cda0bc3"),
        "name" : "joe",
        "age" : 45,
        "Test" : {
                "Date" : "2023-05-04T02:52:25.638-07:00",
                "Status" : "Pending"
        }
}

Running provided query

rs0:PRIMARY> db.getCollection('mycoll').aggregate([ { $match: { _id: /^xx/ } } ], {hint: {_id: 1}, explain: true })
{
        "queryPlanner" : {
                "plannerVersion" : 1,
                "namespace" : "test.mycoll",
                "winningPlan" : {
                        "stage" : "FETCH",
                        "inputStage" : {
                                "stage" : "IXOR",
                                "inputStages" : [
                                        {
                                                "stage" : "IXSCAN",
                                                "indexName" : "_id_"
                                        },
                                        {
                                                "stage" : "IXSCAN",
                                                "indexName" : "_id_"
                                        }
                                ]
                        }
                }
        },
        "serverInfo" : {
                "host" : "checkdb",
                "port" : 27017,
                "version" : "5.0.0"
        },
        "ok" : 1,
        "operationTime" : Timestamp(1698782503, 1)
}

Since complete details are not present their might be few miss in replicating the use case.

To answer your question, we require additional details to replicate your use case for getting better understanding of the issue and help you resolve it. Please open a support case with AWS using the following link [+] https://console.aws.amazon.com/support/home#/case/create

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