Converting table text entries to json?

Question

PostgreSQL

There are hundreds of records in the table in the form of "{\"tags_in\":[393],\"tags_out\":[395]}"a string.

Is it possible to convert them to json {"tags_in":[393],"tags_out":[395]}without losing this data?

Answer 1

update tablename set jsoncol = cast(cast(data as json)#>>'{}' as json);

Answer 2

select '{"tags_in":[393],"tags_out":[395]}'::jsonb