JSONB Cheatsheet

jsonb.sql

-- Copied from https://www.alexedwards.net/blog/using-postgresql-jsonb

-- Create a table with a JSONB column.
CREATE TABLE items (
    id SERIAL PRIMARY KEY,
    attrs JSONB
);

-- You can insert any well-formed json input into the column. Note that only
-- lowercase `true` and `false` spellings are accepted.
INSERT INTO items (attrs) VALUES ('{
   "name": "Pasta",
   "ingredients": ["Flour", "Eggs", "Salt", "Water"],
   "organic": true,
   "dimensions": {
      "weight": 500.00
   }
}');

-- Create an index on all key/value pairs in the JSONB column.
CREATE INDEX idx_items_attrs ON items USING gin (attrs);

-- Create an index on a specific key/value pair in the JSONB column.
CREATE INDEX idx_items_attrs_organic ON items USING gin ((attrs->'organic'));

-- The -> operator is used to get the value for a key. The returned value has
-- the type JSONB.
SELECT attrs->'dimensions' FROM items;
SELECT attrs->'dimensions'->'weight' FROM items;

-- Or you can use ->> to do the same thing, but this returns a TEXT value
-- instead.
SELECT attrs->>'dimensions' FROM items;

-- You can use the returned values as normal, although you may need to type
-- cast them first.
SELECT * FROM items WHERE attrs->>'name' ILIKE 'p%';
SELECT * FROM items WHERE (attrs->'dimensions'->>'weight')::numeric < 100.00;

-- Use ? to check for the existence of a specific key.
SELECT * FROM items WHERE attrs ? 'ingredients';

-- The ? operator only works at the top level. If you want to check for the
-- existence of a nested key you can do this:
SELECT * FROM items WHERE attrs->'dimensions' ? 'weight';

-- The ? operator can also be used to check for the existence of a specific
-- text value in json arrays.
SELECT * FROM items WHERE attrs->'ingredients' ? 'Salt';

-- Use @> to check if the JSONB column contains some specific json. This can
-- be useful to filter for a specific key/value pair like so:
SELECT * FROM items WHERE attrs @> '{"organic": true}'::jsonb;
SELECT * FROM items WHERE attrs @> '{"dimensions": {"weight": 10}}'::jsonb;

-- Note that @> looks for *containment*, not for an exact match. The
-- followingquery will return records which have both "Flour" and "Water"
-- as ingredients, rather than *only* "Flour" and "Water" as the ingredients.
SELECT * FROM items WHERE attrs @> '{"ingredients": ["Flour", "Water"]}'::jsonb;