An element reference allows you to access a specific element of an array. It operates on two arguments: the first must evaluate to an array and the second must evaluate to an integer. The integer refers to the ordinal position of the element in the array (the first element in the array is element number one, the second is element number two, and so on).
It is possible to select the array as a whole value, rather than selecting individual array elements. When the array as a whole is selected, SQL returns a VARCHAR datatype value. That value comprises all the elements, converted to character form, with elements separated from each other by a ";" delimiter.
Example
In this example, the fourth element of the array column named array_column is returned: