在postgres 10中更新jsonb列

Question

I'm trying to update a jsonb column in PG10. I noticed that the following works only if there is some value exists in that column for a given record.

UPDATE public.mytable SET config = jsonb_set (
    config, '{"data1"}', '{ 
        "text" : "my text"
        }', TRUE) 
WHERE id = 1234;

The update is successful only if the column config is not null. I don't see any errors when I execute the statement though.

If this column for a given record is empty, I need to do

UPDATE public.mytable SET config = '{ 
   "data1" : {     
        "text" : "my text"
        }
    }' 
WHERE id = 1234;

So my current strategy is to check for non-null and use first or second method to update the column value. Is this the right approach? Why is the value not updated when I use jsonb_set ?

Answer 1

Use COALESCE(config,'{}')

UPDATE mytable SET config = jsonb_set (
    COALESCE(config,'{}'),'{"data1"}', '{ 
        "text" : "my text"
        }', TRUE) 
WHERE id = 1234;

Demo