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ARRAY_UNION function

Combines two arrays and returns a single array containing all unique values, removing any duplicates. The function is NULL-safe, meaning it treats NULLs are treated as known objects. The order of elements in the result is not guaranteed.

Syntax

ARRAY_UNION( array1, array2 )

Arguments

Return type

The ARRAY_UNION function returns a SUPER type.

Example

The following examples show the ARRAY_UNION function.

SELECT ARRAY_UNION(ARRAY('a','b','b'), ARRAY('b','c','c'));
  array_union  
---------------
 ["a","b","c"]
(1 row)

The order of elements is not guaranteed:

SELECT ARRAY_UNION(ARRAY('b','a','b'), ARRAY(NULL,'b',NULL));
  array_union   
----------------
 ["b","a",null]
(1 row)

See also