How to convert PostgreSQL 9.4's jsonb type to float

Question

I\'m trying the following query:

SELECT (json_data->\'position\'->\'lat\') + 1.0 AS lat FROM updates LIMIT 5;

(The +1.0 is just there

Answer 1

There are two operations to get value from JSON. The first one -> will return JSON. The second one ->> will return text.

Details: JSON Functions and Operators

Try

SELECT (json_data->'position'->>'lat')::float + 1.0 AS lat
FROM updates
LIMIT 5