$bitXor (aggregation)

Definition

$bitXor

Returns the result of a bitwise xor (exclusive or) operation on an array of int and long values.

Syntax

The $bitXor operator has the following syntax:

{ $bitXor: { [ <expression1>, <expression2>, ... ] }

Behavior

If the operands include both integers and long values, MongoDB sign-extends the calculated integer result and returns a long value. Otherwise, if the operands include only integers or only longs, MongoDB returns results with the corresponding value type.

If any arguments in the array are of a different data type such as a string, double, or decimal, MongoDB returns an error.

If the argument is an empty array, the operation returns NumberInt(0).

If any of the arguments in the array equate to null, the operation returns null.

Example

The example on this page uses the switches collection:

db.switches.insertMany( [
    { _id: 0, a: NumberInt(0), b: NumberInt(127) },
    { _id: 1, a: NumberInt(2), b: NumberInt(3) },
    { _id: 2, a: NumberInt(3), b: NumberInt(5) }
] )

The following aggregation uses the $bitXor operator in the $project stage:

db.switches.aggregate( [
  {
    $project: {
      result: {
        $bitXor: ["$a", "$b"]
      }
    }
  }
])

The operation returns the following results:

  [
    { _id: 0, result: 127 },
    { _id: 1, result: 1 },
    { _id: 2, result: 6 }
  ]

Learn More

• Aggregation Pipeline Operators

• $bit