MongoDB Query Language (MQL) Array Expression Operators
$arrayElemAt
The `$arrayElemAt` operator is used to return the element at the specified array index. This operator is helpful when you need to extract a specific element from an array within your documents.
$arrayToObject
The `$arrayToObject` operator converts an array into a single document object. This operator is useful when you need to transform arrays into key-value pairs.
$concatArrays
The `$concatArrays` operator is used to combine multiple arrays into a single array. This operator is useful when you need to merge arrays from different documents or fields in a document.
$filter
The `$filter` operator is used to filter elements from an array based on a specified condition. This operator is useful when you need to manipulate or retrieve specific array elements within documents.
$in
The `$in` operator returns a boolean indicating whether a specified value is in an array.
$indexOfArray
The `$indexOfArray` operator searches an array for an occurrence of a specified value and returns the array index of the first occurrence. If the value is not found, returns -1.
$isArray
The `$isArray` operator determines if the operand is an array. Returns a boolean.
$map
The `$map` operator applies an expression to each item in an array and returns an array with the applied results.
$objectToArray
The `$objectToArray` operator converts a document to an array of documents representing key-value pairs.
$range
The `$range` operator outputs an array containing a sequence of integers according to user-defined inputs.
$reduce
The `$reduce` operator applies an expression to each element in an array and combines them into a single value.
$reverseArray
The `$reverseArray` operator accepts an array expression and returns an array with the elements in reverse order.
$slice
The `$slice` operator returns a subset of an array.
$sortArray
The `$sortArray` operator sorts an array based on its elements or a specified sort order.
$zip
The `$zip` operator transposes an array of input arrays so that the first element of the output array contains an array of the first elements of the input arrays, the second element contains an array of the second elements, and so on.