Purpose: Create a JSON array from a SQL array.


input value:       anyarray
pretty:            boolean (optional)
return value:      json

Notes: This has only a json variant. The first (mandatory) formal parameter is any SQL array whose elements might be compound values. The second formal parameter is optional. When it is true, line feeds are added between dimension-1 elements.

do $body$
  sql_array constant text[] := array['a', 'b', 'c'];

  j_false constant json := array_to_json(sql_array, false);
  j_true  constant json := array_to_json(sql_array, true);

  expected_j_false constant json := '["a","b","c"]';
  expected_j_true  constant json :=
    (j_false::text = expected_j_false::text) and
    (j_true::text  = expected_j_true::text),

The array_to_json() function has no practical advantage over to_json() or to_jsonb() and is restricted because it explicitly handles a SQL array and cannot handle a SQL record (at top level). Moreover, it can produce only a JSON array whose values all have the same data type. If you want to pretty-print the text representation of the result JSON value, you can use the ::text typecast or jsonb_pretty().