postgres=# create table test(id int);
CREATE TABLE
postgres=# insert into test select generate_series(1,20);
INSERT 0 20
postgres=# select * from test;
 id 
----
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
(20 rows)

CREATE OR REPLACE FUNCTION fun_affect_rows()
  RETURNS text AS
$BODY$

declare
v_count int;begin

insert into test values(99),(98);
GET DIAGNOSTICS v_count = ROW_COUNT;
raise notice '本次插入数据量 %',v_count;

delete from test where id < 15;
GET DIAGNOSTICS v_count = ROW_COUNT;
raise notice '本次删除数据量 %',v_count;

update test set id = 100 where id >90;
GET DIAGNOSTICS v_count = ROW_COUNT;
raise notice '本次更新数据量 %',v_count;

return '测试完毕';
end;
$BODY$
  LANGUAGE plpgsql VOLATILE
  COST 100;
ALTER FUNCTION fun_affect_rows()
  OWNER TO postgres;

postgres=# select * from fun_affect_rows();
NOTICE:  本次插入数据量 2
NOTICE:  本次删除数据量 14
NOTICE:  本次更新数据量 2
 fun_affect_rows 
-----------------
 测试完毕
(1 row)