Operators
Accessors
SELECT * FROM users WHERE data->>'name' = 'John';
SELECT data->>'name' AS name FROM users;
Operator | Description | Example | Returns |
---|---|---|---|
-> int |
Get array element 2 |
data->2 |
JSON |
-> text |
Get object key name |
data->'name' |
JSON |
#> text[] |
Get keypath a,b (eg, data.a.b ) |
data#>'{a,b}' |
JSON |
->> int |
Get array element 2 |
data->>2 |
Text |
->> text |
Get object key name |
data->>'name' |
Text |
#>> text[] |
Get keypath a,b (eg, data.a.b ) |
data#>>'{a,b}' |
Text |
>
returns JSON, >>
returns text.
Boolean operators
SELECT * FROM users WHERE data->tags ? 'admin';
SELECT data->tags ? 'admin' AS is_admin FROM users;
Operator | Description | Example |
---|---|---|
? str |
Does data have key name ? |
data ? 'name' |
?| text[] |
Does data have a or b ? |
data ?| array['a','b'] |
?& text[] |
Does data have a and b ? |
data ?& array['a','b'] |
@> jsonb |
Does left include right ? |
data @> '{"b":2}'::jsonb |
<@ jsonb |
Does right include left ? |
data <@ '{"a":1,"b":2}'::jsonb |
When ?
/?|
/?&
works on objects, it checks keys; when it works on arrays, it checks for elements.
Updating
Arrays and objects
UPDATE users SET tags = tags || array['admin'];
Operator | Example | Description |
---|---|---|
|| json |
data || array['a','b'] |
Concatenate |
- str |
data - 'a' |
Delete a key |
- int |
data - 1 |
Delete an array item |
#- text[] |
data #- '{us,name}' |
Delete a path |
Only available in PostgreSQL 9.5+.
jsonb_set
UPDATE users SET data = jsonb_set(data, '{name}', '"John"');
Only available in PostgreSQL 9.5+.
Functions
fn(json) → json
jsonb_set(data, '{path}', value)
jsonb_strip_nulls(data)
fn(···) → json
to_json("Hello"::text)
array_to_json('{1,2}'::int[])
Iteration
SELECT * from json_each('{"a":1, "b":2}')
SELECT * from json_each_text('{"a":1, "b":2}')
-- key | value
This is an incomplete list, there’s way too many!
See: JSON functions
More examples
'{"a":1}'::jsonb ? 'a'
'["a"]'::jsonb ? 'a'
0 Comments for this cheatsheet. Write yours!