Operator does not exist: json = json Operator does not exist: json = json postgresql postgresql

Operator does not exist: json = json


In short - use JSONB instead of JSON or cast JSON to JSONB.

You cannot compare json values. You can compare text values instead:

SELECT * FROM movie_test WHERE tags::text = '["dramatic","women","political"]'

Note however that values of type JSON are stored as text in a format in which they are given. Thus the result of comparison depends on whether you consistently apply the same format:

SELECT     '["dramatic" ,"women", "political"]'::json::text =      '["dramatic","women","political"]'::json::text      -- yields false!    

In Postgres 9.4+ you can solve this problem using type JSONB, which is stored in a decomposed binary format. Values of this type can be compared:

SELECT     '["dramatic" ,"women", "political"]'::jsonb =      '["dramatic","women","political"]'::jsonb           -- yields true

so this query is much more reliable:

SELECT * FROM movie_test WHERE tags::jsonb = '["dramatic","women","political"]'::jsonb

Read more about JSON Types.