set tidb_cost_model_version=1;
drop table if exists t;
create table t(a double, b double);
alter table t add column c_implicit_virtual double as (sqrt(a * a + b * b)), add column c_virtual double as (sqrt(a * a + b * b)) virtual;
alter table t add column c_stored double as (sqrt(a * a + b * b)) stored;
Error 3106: 'Adding generated stored column through ALTER TABLE' is not supported for generated columns.
show create table t;
Table	Create Table
t	CREATE TABLE `t` (
  `a` double DEFAULT NULL,
  `b` double DEFAULT NULL,
  `c_implicit_virtual` double GENERATED ALWAYS AS (sqrt(`a` * `a` + `b` * `b`)) VIRTUAL,
  `c_virtual` double GENERATED ALWAYS AS (sqrt(`a` * `a` + `b` * `b`)) VIRTUAL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin
drop table if exists t;
create table t (c1 tinyint, c2 tinyint generated always as (c1 + 1) virtual);
alter table t modify column c2 int generated always as (c1 + 5) virtual;
drop table if exists t;
create table t (c1 int, c2 int generated always as (c1 + 1) stored, c3 int as (c2 * 2), c4 int as (c2 + 2));
alter table t change c3 c5 int generated always as (c2 * 3), drop c4;
alter table t drop c2;
Error 3108: Column 'c2' has a generated column dependency.
alter table t change c2 c6 int generated always as (c1 + 1) stored;
Error 3108: Column 'c2' has a generated column dependency.
drop table if exists t;
create table t (a int, b int, c int, index(c));
alter table t modify column b int generated always as (a + 1) virtual;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t modify column b int generated always as (a + 1) stored;
Error 3106: 'modifying a stored column' is not supported for generated columns.
alter table t change column b b1 int generated always as (a + 1) virtual;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t change column b b1 int generated always as (a + 1) stored;
Error 3106: 'modifying a stored column' is not supported for generated columns.
alter table t modify column c int generated always as (a + 1) virtual;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t modify column c int generated always as (a + 1) stored;
Error 3106: 'modifying a stored column' is not supported for generated columns.
alter table t change column c c1 int generated always as (a + 1) virtual;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t change column c c1 int generated always as (a + 1) stored;
Error 3106: 'modifying a stored column' is not supported for generated columns.
drop table if exists t;
create table t (
a int,
b int generated always as (a + 1) virtual,
c int generated always as (a + 1) virtual,
d int generated always as (a + 1) virtual,
e int generated always as (a + 1) virtual
);
alter table t add index (c), add index (e);
alter table t modify column b int;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t modify column c int;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t change column b b1 int;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t change column c c1 int;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t modify column b int generated always as (a + 10) virtual;
show create table t;
Table	Create Table
t	CREATE TABLE `t` (
  `a` int(11) DEFAULT NULL,
  `b` int(11) GENERATED ALWAYS AS (`a` + 10) VIRTUAL,
  `c` int(11) GENERATED ALWAYS AS (`a` + 1) VIRTUAL,
  `d` int(11) GENERATED ALWAYS AS (`a` + 1) VIRTUAL,
  `e` int(11) GENERATED ALWAYS AS (`a` + 1) VIRTUAL,
  KEY `c` (`c`),
  KEY `e` (`e`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin
alter table t modify column c int generated always as (a + 10) virtual;
Error 3106: 'modifying an indexed column' is not supported for generated columns.
alter table t change column b b1 int generated always as (a + 100) virtual;
show create table t;
Table	Create Table
t	CREATE TABLE `t` (
  `a` int(11) DEFAULT NULL,
  `b1` int(11) GENERATED ALWAYS AS (`a` + 100) VIRTUAL,
  `c` int(11) GENERATED ALWAYS AS (`a` + 1) VIRTUAL,
  `d` int(11) GENERATED ALWAYS AS (`a` + 1) VIRTUAL,
  `e` int(11) GENERATED ALWAYS AS (`a` + 1) VIRTUAL,
  KEY `c` (`c`),
  KEY `e` (`e`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin
alter table t change column c c1 int generated always as (a + 100) virtual;
alter table t modify column d int generated always as (a + 10) stored;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t modify column e int generated always as (a + 10) stored;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t change column d d1 int generated always as (a + 10) stored;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t change column e e1 int generated always as (a + 10) stored;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
drop table if exists t;
create table t (
a int,
b int generated always as (a + 1) stored,
c int generated always as (a + 1) stored,
d int generated always as (a + 1) stored,
e int generated always as (a + 1) stored
);
alter table t add index (c), add index (e);
alter table t modify column b int, modify column c int;
alter table t change column d d1 int, change column e e1 int;
show create table t;
Table	Create Table
t	CREATE TABLE `t` (
  `a` int(11) DEFAULT NULL,
  `b` int(11) DEFAULT NULL,
  `c` int(11) DEFAULT NULL,
  `d1` int(11) DEFAULT NULL,
  `e1` int(11) DEFAULT NULL,
  KEY `c` (`c`),
  KEY `e` (`e1`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin
drop table if exists t;
create table t (a int,
b int generated always as (a + 1) stored,
c int generated always as (a + 1) stored,
index(c)
);
alter table t modify column b int generated always as (a + 10) virtual;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t modify column c int generated always as (a + 10) virtual;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t change column b b1 int generated always as (a + 10) virtual;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t change column c c1 int generated always as (a + 10) virtual;
Error 3106: 'Changing the STORED status' is not supported for generated columns.
alter table t modify column b int generated always as (a + 10) stored;
Error 3106: 'modifying a stored column' is not supported for generated columns.
alter table t modify column c int generated always as (a + 10) stored;
Error 3106: 'modifying a stored column' is not supported for generated columns.
alter table t change column b b1 int generated always as (a + 10) stored;
Error 3106: 'modifying a stored column' is not supported for generated columns.
alter table t change column c c1 int generated always as (a + 10) stored;
Error 3106: 'modifying a stored column' is not supported for generated columns.