drop table if exists t1;
create table t1(
id int(11) NOT NULL,
c1 int(11) DEFAULT NULL,
c2 int(11) DEFAULT NULL,
PRIMARY KEY(id),
KEY idx_c1c2(c1, c2)
)ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;
Warnings:
Warning	1681	Integer display width is deprecated and will be removed in a future release.
Warning	1681	Integer display width is deprecated and will be removed in a future release.
Warning	1681	Integer display width is deprecated and will be removed in a future release.
drop procedure if exists insert_data;
CREATE PROCEDURE insert_data(start int, end int)
BEGIN
DECLARE i int DEFAULT 0;
DECLARE a int DEFAULT 0;
DECLARE b int DEFAULT 0;
set i=start;
WHILE i<end
DO
SELECT FLOOR(RAND()*(1000000-0+1)+0) into a;
SELECT FLOOR(RAND()*(1000000-0+1)+0) into b;
INSERT INTO t1(id,c1,c2) VALUES(i,a,b);
set i=i+1;
END WHILE;
END//
call insert_data(0,5000);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
call insert_data(5000,10000);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
call insert_data(10000,15000);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
call insert_data(15000,20000);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
select count(*) from t1;
count(*)
20000
alter table t1 add index idx_c1_c2(c1,c2);
show create table t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `id` int(11) NOT NULL,
  `c1` int(11) DEFAULT NULL,
  `c2` int(11) DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `idx_c1c2` (`c1`,`c2`),
  KEY `idx_c1_c2` (`c1`,`c2`)
) ENGINE=XENGINE DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
drop table if exists t1;
drop procedure if exists insert_data;