drop table if exists t1,t2;
create table t1 (a int, b int, v int as (a+1), index idx(b));
insert into t1(a, b) values
(4, 40), (3, 30), (5, 50), (7, 70), (8, 80), (2, 20), (1, 10);
select * from t1 order by b;
a	b	v
1	10	2
2	20	3
3	30	4
4	40	5
5	50	6
7	70	8
8	80	9
delete from t1 where v > 6 order by b limit 1;
select * from t1 order by b;
a	b	v
1	10	2
2	20	3
3	30	4
4	40	5
5	50	6
8	80	9
update t1 set a=v order by b limit 1;
select * from t1 order by b;
a	b	v
2	10	3
2	20	3
3	30	4
4	40	5
5	50	6
8	80	9
drop table t1;
CREATE TABLE t1 (
a int NOT NULL DEFAULT '0',
v double AS ((1, a)) VIRTUAL
);
ERROR HY000: Expression for computed column cannot return a row
CREATE TABLE t1 (
a CHAR(255) BINARY NOT NULL DEFAULT 0,
b CHAR(255) BINARY NOT NULL DEFAULT 0,
v CHAR(255) BINARY AS (CONCAT(a,b)) VIRTUAL );
INSERT INTO t1(a,b) VALUES ('4','7'), ('4','6');
SELECT 1 AS C FROM t1 ORDER BY v;
C
1
1
DROP TABLE t1;
CREATE TABLE t1(a int, b int DEFAULT 0, v INT AS (b+10) PERSISTENT);
INSERT INTO t1(a) VALUES (1);
SELECT b, v FROM t1;
b	v
0	10
DROP TABLE t1;
CREATE TABLE t1(a int DEFAULT 100, v int AS (a+1) PERSISTENT);
INSERT INTO t1 () VALUES ();
CREATE TABLE t2(a int DEFAULT 100 , v int AS (a+1));
INSERT INTO t2 () VALUES ();
SELECT a, v FROM t1;
a	v
100	101
SELECT a, v FROM t2;
a	v
100	101
DROP TABLE t1,t2;
CREATE TABLE t1 (
a datetime NOT NULL DEFAULT '2000-01-01',
v boolean AS (a < '2001-01-01')
);
INSERT INTO t1(a) VALUES ('2002-02-15');
INSERT INTO t1(a) VALUES ('2000-10-15');
SELECT a, v FROM t1;
a	v
2002-02-15 00:00:00	0
2000-10-15 00:00:00	1
SELECT a, v FROM t1;
a	v
2002-02-15 00:00:00	0
2000-10-15 00:00:00	1
CREATE TABLE t2 (
a datetime NOT NULL DEFAULT '2000-01-01',
v boolean AS (a < '2001-01-01') PERSISTENT
);
INSERT INTO t2(a) VALUES ('2002-02-15');
INSERT INTO t2(a) VALUES ('2000-10-15');
SELECT * FROM t2;
a	v
2002-02-15 00:00:00	0
2000-10-15 00:00:00	1
DROP TABLE t1, t2;
CREATE TABLE t1 (
a char(255), b char(255), c char(255), d char(255),
v char(255) AS (CONCAT(c,d) ) VIRTUAL
);
INSERT INTO t1(a,b,c,d) VALUES ('w','x','y','z'), ('W','X','Y','Z');
SELECT v FROM t1 ORDER BY CONCAT(a,b);
v
yz
YZ
DROP TABLE t1;
CREATE TABLE t1 (f1 INTEGER, v1 INTEGER AS (f1) VIRTUAL);
CREATE TABLE t2 AS SELECT v1 FROM t1;
SHOW CREATE TABLE t2;
Table	Create Table
t2	CREATE TABLE `t2` (
  `v1` int(11) DEFAULT NULL
) ENGINE=MyISAM DEFAULT CHARSET=latin1
DROP TABLE t1,t2;
CREATE TABLE t1 (p int, a double NOT NULL, v double AS (ROUND(a,p)) VIRTUAL);
INSERT INTO t1 VALUES (0,1,0);
Warnings:
Warning	1718	The value specified for computed column 'v' in table 't1' ignored
INSERT INTO t1 VALUES (NULL,0,0);
Warnings:
Warning	1718	The value specified for computed column 'v' in table 't1' ignored
SELECT a, p, v, ROUND(a,p), ROUND(a,p+NULL) FROM t1;
a	p	v	ROUND(a,p)	ROUND(a,p+NULL)
1	0	1	1	NULL
0	NULL	NULL	NULL	NULL
DROP TABLE t1;
CREATE TABLE t1 (p int, a double NOT NULL);
INSERT INTO t1(p,a) VALUES (0,1);
INSERT INTO t1(p,a) VALUES (NULL,0);
SELECT a, p, ROUND(a,p), ROUND(a,p+NULL) FROM t1;
a	p	ROUND(a,p)	ROUND(a,p+NULL)
1	0	1	NULL
0	NULL	NULL	NULL
DROP TABLE t1;
CREATE TABLE t1 (a char(32), v char(32) CHARACTER SET ucs2 AS (a) VIRTUAL);
SHOW CREATE TABLE t1;
Table	Create Table
t1	CREATE TABLE `t1` (
  `a` char(32) DEFAULT NULL,
  `v` char(32) CHARACTER SET ucs2 AS (a) VIRTUAL
) ENGINE=MyISAM DEFAULT CHARSET=latin1
DROP TABLE t1;
create table t1 (a int, b int);
insert into t1 values (3, 30), (4, 20), (1, 20);
create table t2 (c int, d int, v int as (d+1), index idx(c));
insert into t2(c,d) values 
(20, 100), (20, 300), (30, 100), (30, 200), (40, 500),
(70, 100), (40, 300), (60, 100), (40, 100), (70, 100);
set join_cache_level=6;
explain
select * from t1,t2 where t1.b=t2.c and d <= 100;
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	
1	SIMPLE	t2	ref	idx	idx	5	test.t1.b	2	Using where; Using join buffer
select * from t1,t2 where t1.b=t2.c and d <= 100;
a	b	c	d	v
4	20	20	100	101
1	20	20	100	101
3	30	30	100	101
set join_cache_level=default;
drop table t1, t2;