In SQLite I can get a single row whose value is a JSON array of objects of each row.

SELECT 
    json_group_array(json_object('col1', col1, 'col2', col2)) as data 
FROM table1;

returns

|data|
|'[{"col1": ..., "col2": ...}, {"col1": ..., "col2": ...}, {"col1": ..., "col2": ...}]'|

However, the json_object('col1', col1, 'col2', col2) is a little bit unwieldy and gets worse when there is more columns in the query.

1. Why isn’t is possible to use json_object(*) (just returns ‘{}’)?
2. Is there an alternative?