drop table if exists t1,t2;
create table t1 (a int, b varchar(200), c text not null) checksum=1;
create table t2 (a int, b varchar(200), c text not null) checksum=0;
insert t1 values (1, "aaa", "bbb"), (NULL, "", "ccccc"), (0, NULL, "");
insert t2 select * from t1;
checksum table t1, t2;
Table	Checksum
test.t1	2948697075
test.t2	2948697075
checksum table t1, t2 quick;
Table	Checksum
test.t1	NULL
test.t2	NULL
checksum table t1, t2 extended;
Table	Checksum
test.t1	2948697075
test.t2	2948697075
drop table t1,t2;
SHOW PROCESSLIST;
Id	User	Host	db	Command	Time	State	Info
<Id>	root	<Host>	test	Query	<Time>	NULL	SHOW PROCESSLIST