For the number of bytes used to store:
select id, pg_column_size(datab) from data.items;
For the number of elements on the jsonb object:
select id, jsonb_array_length(datab) from data.items;
For the number of bytes used to store:
select id, pg_column_size(datab) from data.items;
For the number of elements on the jsonb object:
select id, jsonb_array_length(datab) from data.items;