Creating JSON

JSON Creation Functions

The following functions are used to create JSON.

Function	Description
to_json(any)	Create JSON from a value of any type. Our LIST is converted to a JSON array, and our STRUCT and MAP are converted to a JSON object.
json_quote(any)	Alias for to_json.
array_to_json(list)	Alias for to_json that only accepts LIST.
row_to_json(list)	Alias for to_json that only accepts STRUCT.
json_array(any, ...)	Create a JSON array from the values in the argument lists.
json_object(key, value, ...)	Create a JSON object from key, value pairs in the argument list. Requires an even number of arguments.
json_build_array(any, ...)	Alias for json_array, under its PostgreSQL name.
json_build_object(key, value, ...)	Alias for json_object, under its PostgreSQL name.
json_merge_patch(json, json)	Merge two JSON documents together.

Examples:

SQL

SELECT to_json('mercury');

 to_json
-----------
 "mercury"

SQL

SELECT to_json([1, 2, 3]);

 to_json
---------
 [1,2,3]

SQL

SELECT to_json({mercury : 42});

 to_json
----------------
 {"mercury":42}

SQL

SELECT to_json(MAP(['mercury'], [42]));

 to_json
----------------
 {"mercury":42}

SQL

SELECT json_array('mercury', 42, 'venus', 123);

 json_array
----------------------------
 ["mercury",42,"venus",123]

SQL

SELECT json_object('mercury', 42, 'venus', 123);

 json_object
----------------------------
 {"mercury":42,"venus":123}

SQL

SELECT json_merge_patch('{"mercury": 42}', '{"venus": 123}');

 json_merge_patch
----------------------------
 {"mercury":42,"venus":123}