MongoDB find document with Date field using a part of Date

Question

i want to search a date like the following:

09-11
03-22

and it will search in the available documents and bring the matched documnet. an available document example :

2022-09-11T15:31:25.083+00:00

how can i do this?

i tried following query but that didn't work:

db.users.find({ createdAt: new RegExp('09-11') }) // Null

Answer 1

You can do it with aggregate query:

• $toString - to convert date to string
• $regexMatch - to apply regex search

db.collection.aggregate([
  {
    "$match": {
      "$expr": {
        "$regexMatch": {
          "input": {
            "$toString": "$createdAt"
          },
          "regex": "09-11"
        }
      }
    }
  }
])

Working example