CREATE TABLE t1 (
  f2 INT,
  pk2 INT,
  f1 VARCHAR(3),
  pk1 VARCHAR(1000),
  PRIMARY KEY (pk1,pk2),
  KEY k1(pk1,f2)
) ENGINE=InnoDB CHARSET utf8;

INSERT INTO t1 VALUES (1,2,'2','abc'),(2,3,'3','def');
explain format= json
select * from t1 force index(k1)  where f2 <= 5 and pk2 <=5 and pk1 = 'abc' and f1 <= '3';
drop table t1;