Here is my statement:

SELECT 
    "raw_storage_basetransaction"."id",
    "raw_storage_basetransaction"."r_v", 
    "raw_storage_basetransaction"."transaction_data", 
    "raw_storage_basetransaction"."entry_datetime", 
    "raw_storage_basetransaction"."owner_id",
    ("transaction_data" ->> 'SupplierDB') AS "v"
FROM 
    "raw_storage_basetransaction" 
LIMIT 21

or

SELECT
    "raw_storage_basetransaction"."id",
    "raw_storage_basetransaction"."r_v", 
    "raw_storage_basetransaction"."transaction_data", 
    "raw_storage_basetransaction"."entry_datetime", 
    "raw_storage_basetransaction"."owner_id", 
    ("raw_storage_basetransaction"."transaction_data" ->> 'SupplierDB') AS "v" 
FROM 
    "raw_storage_basetransaction" 
LIMIT 21

v is always NULL

What did I do wrong?

--UPD--

My fault. I wrote in jsonb field a unicode string instead of json-dict.