ARRAY_DISTINCT

Description

The ARRAY_DISTINCT function is used to remove duplicate elements from an array, returning an array without duplicates. This function can handle arrays of any type, including integers, floating-point numbers, strings, etc.

Syntax

ARRAY_DISTINCT(array)

Parameter Description

• array: array<T> type, represents the array that needs to be deduplicated.

Return Result

Returns a result of type array<T>, which contains the deduplicated array elements.

Usage Example

1. Remove duplicates from an integer array:

SELECT ARRAY_DISTINCT(ARRAY(1, 2, 2, 3));
-- Return result：[1, 2, 3]

2. Remove duplicates from an array of floating-point numbers:

SELECT ARRAY_DISTINCT(ARRAY(3.14, 2.71, 2.71, 1.41));
-- Return result: [3.14, 2.71, 1.41]

3. Remove duplicates from a string array:

SELECT ARRAY_DISTINCT(ARRAY('apple', 'orange', 'apple', 'banana'));
-- Return result: ['apple', 'orange', 'banana']

4. Remove duplicates from a mixed-type array:

SELECT ARRAY_DISTINCT(ARRAY(1, 'a', 2, 'b', 1, 'a', 3));
-- Return result: [1,null,2,3]

Notes

• When the array is empty, the ARRAY_DISTINCT function will return an empty array.