unique()

Returns an array with duplicate elements removed.

Syntax

unique(ARRAY)

Parameters

ARRAY: The array or collection from which to remove duplicate elements. If a single value is specified, an array containing only that value is returned.

Description

The unique() function removes duplicate elements from the input array and returns an array containing only unique elements. Duplicate detection is based on element equality.

The order of elements in the returned array is not guaranteed. If a single non-array value is passed as an argument, an array containing only that value is returned. If the input is null, null is returned.

Error codes

N/A

Usage examples

Remove duplicate elements from an array (order of returned elements is not guaranteed)
```
json "{}" | eval result = unique(array(1, 1, 2, 3, 2))
| # result: [1, 2, 3]
```

Values of different types are treated as distinct elements

json "{}" | eval result = unique(array(1, "1", 2, "2"))
| # result: [1,"1",2,"2"]

Passing a single value returns an array containing only that value
```
json "{}" | eval result = unique("hello")
| # result: ["hello"]
```

null input

json "{}" | eval result = unique(null)
| # result: null

Compatibility

unique() has been available since before Sonar 4.0.