# How to Compare Arrays in PostgreSQL

The equality operators (`=, <>`) do an exact element-by-element comparison.

``````select
array[1,2,3] = array[1,2,4] as compare1, -- arrays are equal
array[1,2,3] <> array[1,2,4] as compare2; -- arrays are not equal
``````
`compare1` `compare2`
`John` `1.85`
`Mary` `1.65`

The ordering operators (`>, <, >=, <=`) also compare each element in an array in order. Results are based on the first different pair of elements, not the sizes of the arrays.

``````select
array[1,2,5] >= array[1,2,4] as compare1,
array[1,2,5] <= array[1,2,4,5] as compare2;
``````
`compare1` `compare2`
`t` `f`

Then there are the containment operators (`@>, <@`). They are casually called “bird operators”, well, because `@>` looks like a bird. An array is said to be contained in another array if each of its unique elements is also present in the other array.

``````-- This reads as array['a', 'b', 'c'] contains array['a', 'b', 'b', 'a']
select array['a', 'b', 'c'] @> array['a', 'b', 'b', 'a'] as contains;
``````
`contains`
`t`
``````-- This reads as array[1, 1, 4] is contained by array[4, 3, 2, 1]
select array[1, 1, 4] <@ array[4, 3, 2, 1] as is_contained_by;
``````
`is_contained_by`
`T`

Lastly, there is the overlap operator (`&&`). Arrays that have elements in common are called overlapping arrays. To check if two arrays overlap, use the `&&` operator:

``````select
array[1, 2] && array[2, 3] as overlap1,
array[1, 2] && array[3, 4] as overlap2;
``````
`overlap1` `overlap2`
`t` `f`