Finding MongoDB regex by integer value

Question

I want the regex to look for an integer value in MongoDB. Is it possible?

I am creating an interface of type CRUD that allows * for wildcards in different fields. I try to keep the user interface consistent across multiple fields that are integers.

Consider:

> db.seDemo.insert({ "example" : 1234 });
> db.seDemo.find({ "example" : 1234 });
{ "_id" : ObjectId("4bfc2bfea2004adae015220a"), "example" : 1234 }
> db.seDemo.find({ "example" : /^123.*/ });
> 

As you can see, I am inserting an object, and I can find it by value. If I try a simple regular expression, I cannot find the object.

Thank!

Answer 1

, mongo - $where .

> db.test.find({ $where: "/^123.*/.test(this.example)" })
{ "_id" : ObjectId("4bfc3187fec861325f34b132"), "example" : 1234 }

Answer 2

$where - , , , .

MongoDB 4.2 $regexMatch|$regexFind|$regexFindAll MongoDB 4.1. 9+, $expr .

let regex = /123/;

• $regexMatch $regexFind

  db.col.find({
      "$expr": {
          "$regexMatch": {
             "input": {"$toString": "$name"}, 
             "regex": /123/ 
          }
      }
  })
  

• $regexFinAll

  db.col.find({
      "$expr": {
          "$gt": [
              { 
                  "$size": { 
                      "$regexFindAll": { 
                          "input": {"$toString": "$name"}, 
                          "regex": "123" 
                      }
                  }
              }, 
              0
          ]
      }
  })
  

---

MongoDB 4.0 $toString $convert $convert .

db.seDemo.aggregate([ 
    { "$redact": { 
        "$cond": [ 
            { "$gt": [ 
                { "$indexOfCP": [ 
                    { "$toString": "$example" }, 
                    "123" 
                ] }, 
                -1 
            ] }, 
            "$$KEEP", 
            "$$PRUNE" 
        ] 
    }}
])

, , 3.4, $redact $cond. $indexOfCP.

db.seDemo.aggregate([ 
    { "$redact": { 
        "$cond": [ 
            { "$gt": [ 
                { "$indexOfCP": [ 
                    { "$toLower": "$example" }, 
                    "123" 
                ] }, 
                -1 
            ] }, 
            "$$KEEP", 
            "$$PRUNE" 
        ] 
    }}
])

:

{ 
    "_id" : ObjectId("579c668c1c52188b56a235b7"), 
    "example" : 1234 
}

{ 
    "_id" : ObjectId("579c66971c52188b56a235b9"), 
    "example" : 12334 
}

---

MongoDB 3.4 $project $project , .

$toLower $toUpper , , , .

$match , , $regex.

db.seDemo.aggregate(
    [ 
        { "$project": { 
            "stringifyExample": { "$toLower": "$example" }, 
            "example": 1 
        }}, 
        { "$match": { "stringifyExample": /^123.*/ } }
    ]
)

:

{ 
    "_id" : ObjectId("579c668c1c52188b56a235b7"), 
    "example" : 1234,
    "stringifyExample" : "1234"
}

{ 
    "_id" : ObjectId("579c66971c52188b56a235b9"), 
    "example" : 12334,
    "stringifyExample" : "12334"
}

---

, , , MongoDB ( ) $redact $cond itional . $indexOfCP.

db.seDemo.aggregate([ 
    { "$redact": { 
        "$cond": [ 
            { "$gt": [ 
                { "$indexOfCP": [ 
                    { "$toLower": "$example" }, 
                    "123" 
                ] }, 
                -1 
            ] }, 
            "$$KEEP", 
            "$$PRUNE" 
        ] 
    }}
])