sql找出两张表中的不同

需求：

有两张相同结构的表，一个数据多，一个数据少，将两张表中不同的数据找出来并且插入到数据少的表里面

INSERT INTO "public"."waterqualmonitsection" ( "name", "info", "province", "longitude", "latitude", "river", "basin", "city", "status" ) 
SELECT
b.NAME AS NAME,
b.info AS info,
b.province AS province,
b.longitude AS longitude,
b.latitude AS latitude,
b.river AS river,
b.basin AS basin,
b.city AS city,
b.status AS status 
FROM
    waterqualmonitsectionnn b 
WHERE
    NOT EXISTS ( SELECT 1 FROM waterqualmonitsection A WHERE A.NAME = b.NAME AND A.province = b.province )