COPY FROM
COPY table_name FROM 'file_path' (NULL 'string')
null,5 2,2 3,2
CREATE TABLE idqty (id INTEGER, quantity INTEGER);
COPY idqty FROM idvals (NULL, 'null');
+------+----------+ | id | quantity | +------+----------+ | | 5 | | 2 | 2 | | 3 | 2 | +------+----------+
“null”,5 2,2 3,“null”
+------+----------+ | id | quantity | +------+----------+ | null | 5 | | 2 | 2 | | 3 | null | +------+----------+