CREATE EXTENSION zson;
SELECT zson_extract_strings('true');
 zson_extract_strings 
----------------------
 {}
(1 row)

SELECT zson_extract_strings('"aaa"');
 zson_extract_strings 
----------------------
 {aaa}
(1 row)

SELECT zson_extract_strings('["some", ["dummy", "array"], 456, false]');
 zson_extract_strings 
----------------------
 {some,dummy,array}
(1 row)

SELECT zson_extract_strings('{"IP":"10.0.0.3","Roles":["master", "slave"]}');
       zson_extract_strings       
----------------------------------
 {IP,Roles,10.0.0.3,master,slave}
(1 row)

CREATE TABLE nocompress(x jsonb);
INSERT INTO nocompress VALUES
('true'),
('123'),
('"aaa"'),
('["some", ["dummy", "array"], 456, false]'),
('
[
{"ModifyIndex":1,"IP":"10.0.0.1","Roles":["master"]},
{"ModifyIndex":2,"IP":"10.0.0.2","Roles":["slave"]},
{"ModifyIndex":3,"IP":"10.0.0.3","Roles":["master", "slave"]}
]
');
SELECT zson_learn('{{"nocompress", "x"}}');
                                  zson_learn                                   
-------------------------------------------------------------------------------
 Done! Run " select * from zson_dict where dict_id = 0; " to see a dictionary.
(1 row)

SELECT dict_id, word FROM zson_dict ORDER BY dict_id, word COLLATE "C";
 dict_id |    word     
---------+-------------
       0 | IP
       0 | ModifyIndex
       0 | Roles
       0 | master
       0 | slave
(5 rows)

SELECT zson_learn('{{"nocompress", "x"}}', 10000, 1, 128, 1);
                                  zson_learn                                   
-------------------------------------------------------------------------------
 Done! Run " select * from zson_dict where dict_id = 1; " to see a dictionary.
(1 row)

SELECT dict_id, word FROM zson_dict ORDER BY dict_id, word COLLATE "C";
 dict_id |    word     
---------+-------------
       0 | IP
       0 | ModifyIndex
       0 | Roles
       0 | master
       0 | slave
       1 | 10.0.0.1
       1 | 10.0.0.2
       1 | 10.0.0.3
       1 | IP
       1 | ModifyIndex
       1 | Roles
       1 | aaa
       1 | array
       1 | dummy
       1 | master
       1 | slave
       1 | some
(17 rows)

SELECT '{"aaa": "ololo"}'::zson;
       zson       
------------------
 {"aaa": "ololo"}
(1 row)

SELECT '{"aaa": "ololo"}'::zson -> 'aaa';
 ?column? 
----------
 "ololo"
(1 row)

CREATE TABLE zson_test(x zson);
INSERT INTO zson_test VALUES('{"aaa":123}' :: jsonb);
SELECT dict_id, word FROM zson_dict ORDER BY dict_id, word COLLATE "C";
 dict_id |    word     
---------+-------------
       0 | IP
       0 | ModifyIndex
       0 | Roles
       0 | master
       0 | slave
       1 | 10.0.0.1
       1 | 10.0.0.2
       1 | 10.0.0.3
       1 | IP
       1 | ModifyIndex
       1 | Roles
       1 | aaa
       1 | array
       1 | dummy
       1 | master
       1 | slave
       1 | some
(17 rows)

SELECT x :: jsonb FROM zson_test;
      x       
--------------
 {"aaa": 123}
(1 row)

DROP TABLE zson_test;
DROP TABLE nocompress;
DROP EXTENSION zson;