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$minN

Definition

Returns a new array without changing the source list.

Expression operator · Arrays · Studio Visual: available. Studio validates the complete expression separately.

Syntax

{
  "$minN": {
    "input": <input>,
    "n": <n>
  }
}

Replace angle-bracket placeholders with expressions or values.

Optional parameters may be omitted.

Parameters

Parameter Required Description
input Yes Expression supplying the value to process. A field reference such as "$price" reads from the current document.
n Yes Positive integer count of elements to return.

Behavior

The following observations use the example expression below. Each row substitutes one argument while retaining the other example arguments. A missing field differs from an explicit null; the result shown is what Core actually returned.

For the input argument:

Input case Supplied value Result
null null Error — $minN input must be an array
missing Field absent Error — $minN input must be an array
decimal 2.5 Error — $minN input must be an array
numeric string "12" Error — $minN input must be an array
text "hello" Error — $minN input must be an array
boolean true Error — $minN input must be an array
typed date {"$date":"2026-01-15T15:00:00Z"} Error — $minN input must be an array
empty array [] []
numeric array [1,2,3] [1,2]
object {"x":1} Error — $minN input must be an array

Argument handling

Invocation Result
{"$minN":[]} Error — $minN requires input and n
{"$minN":{"unexpected":1}} Error — $minN requires input and n

Examples

Expression: 

{
  "$minN": {
    "input": [
      3,
      1,
      2
    ],
    "n": 2
  }
}

Input document: 

{}

Observed SrotaX result: [1,2].

Detailed input cases

Expand the complete argument-by-argument test matrix

Each table changes only the indicated argument from the example above. Other arguments retain their baseline values. Values normally come from the input field probe; literal configuration arguments are replaced directly. “Missing” means the field is absent, not explicitly null. Numeric strings are strings, not numbers.

Argument: input

Input case Supplied value SrotaX result
null null Error — $minN input must be an array
missing Field absent Error — $minN input must be an array
zero 0 Error — $minN input must be an array
negative -2 Error — $minN input must be an array
decimal 2.5 Error — $minN input must be an array
numeric string "12" Error — $minN input must be an array
text "hello" Error — $minN input must be an array
empty string "" Error — $minN input must be an array
boolean true Error — $minN input must be an array
false false Error — $minN input must be an array
typed date {"$date":"2026-01-15T15:00:00Z"} Error — $minN input must be an array
decimal128 {"$numberDecimal":"1.25"} Error — $minN input must be an array
empty array [] []
numeric array [1,2,3] [1,2]
mixed array [1,null,"x",3] [1,3]
nested array [[1,2],[3]] [[1,2],[3]]
empty object {} Error — $minN input must be an array
object {"x":1} Error — $minN input must be an array
ISO date string "2026-01-15T15:00:00Z" Error — $minN input must be an array
omitted named argument Argument removed Error — $minN requires input and n

Argument: n

Input case Supplied value SrotaX result
null null Error — $minN n must be a positive 64-bit integer
missing Field absent Error — $minN n must be a positive 64-bit integer
zero 0 Error — $minN n must be a positive 64-bit integer
negative -2 Error — $minN n must be a positive 64-bit integer
decimal 2.5 Error — $minN n must be a positive 64-bit integer
numeric string "12" Error — $minN n must be a positive 64-bit integer
text "hello" Error — $minN n must be a positive 64-bit integer
empty string "" Error — $minN n must be a positive 64-bit integer
boolean true Error — $minN n must be a positive 64-bit integer
false false Error — $minN n must be a positive 64-bit integer
typed date {"$date":"2026-01-15T15:00:00Z"} Error — $minN n must be a positive 64-bit integer
decimal128 {"$numberDecimal":"1.25"} Error — $minN n must be a positive 64-bit integer
empty array [] Error — $minN n must be a positive 64-bit integer
numeric array [1,2,3] Error — $minN n must be a positive 64-bit integer
mixed array [1,null,"x",3] Error — $minN n must be a positive 64-bit integer
nested array [[1,2],[3]] Error — $minN n must be a positive 64-bit integer
empty object {} Error — $minN n must be a positive 64-bit integer
object {"x":1} Error — $minN n must be a positive 64-bit integer
ISO date string "2026-01-15T15:00:00Z" Error — $minN n must be a positive 64-bit integer
omitted named argument Argument removed Error — $minN requires input and n

Verification

This page records 43 executed cases. It covers individual argument substitutions, not every cross-product of arguments, locale, daylight-saving transitions, numeric overflow, collation or resource limits. No untested behavior is guaranteed.

Download exact expressions, inputs and SrotaX results. Errors are observed messages, not stable public error codes. The reference generator reads the checked-in execution report; do not edit generated observations by hand.

MongoDB differences

Compared with MongoDB 9.0.4: 5 exact BSON matches, 38 both rejected, 0 value/type/acceptance differences, 0 object-field-order differences.

“Exact” includes numeric BSON types and object key order. A value of 3 as int32 differs from 3.0 as double. Object-field-order differences are reported separately; object key ordering is not enforced by the engine regression baseline. Both rejected does not mean the error codes or messages match. This is finite-case evidence, not full compatibility certification.

No differences were observed in the compared cases.

Download full comparison evidence.