Postgres multiple columns to json
There is a better option with json_build_object() in Postgres 9.4+:

SELECT id, json_build_object('name', name, 'addr', addr) AS data
FROM   myt;


But there is also a simpler and faster way with row_to_json() in Postgres 9.3:

SELECT id, row_to_json((SELECT d FROM (SELECT name, addr) d)) AS data
FROM   myt;


db&lt;>fiddle here
Old SQL Fiddle on Postgres 9.6.

Related answers:


Select columns inside json_agg
Return as array of JSON objects in SQL (Postgres)
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