Below is an alphabetical list of functions that we can use when working with arrays in PostgreSQL.

Function	Description
array_append()	Appends an element to the end of an array.
array_cat()	Concatenates two arrays.
array_dims()	Returns information about the dimensions in an array.
array_fill()	Creates an array filled multiple instances of a given value.
array_length()	Returns the length of the specified array dimension.
array_lower()	Returns the lower bound of the specified array dimension.
array_ndims()	Returns the number of dimensions of an array.
array_position()	Returns the position of the first occurrence of a given value in an array.
array_positions()	Returns the position of the all occurrences of a given value in an array.
array_prepend()	Prepends an element to the start of an array.
array_remove()	Removes elements from an array.
array_replace()	Replaces a specified element (or elements) in an array with another element.
array_sample()	Returns an array of a specified number of items randomly selected from the given array.
array_shuffle()	Randomly shuffles the first dimension of a given array.
array_to_string()	Converts an array to a string.
array_upper()	Returns the upper bound of the specified array dimension.
cardinality()	Returns the total number of elements in an array. This includes elements across all dimensions of the array.
trim_array()	Trims a given number of elements from the end of an array.
unnest()	Expands an array into a set of rows.