求一SQL语句修改类型为text的列到char(255)!----------------------
--2005.
create table tb(a text)
insert into tb values ('aaaaaa')
goalter table tb alter column a char(255)
goselect * from tbdrop table tb/*
a
------------
aaaaaa
(1 行受影响)
*/-----------------------
--2000
create table tb(a text)
insert into tb values ('aaaaaa')
go--加个列B
alter table tb add b char(255)
go
--将B设置为A的值
update tb set b = cast(a as varchar)
go
--删除A
alter table tb drop column a
go
--更改列名B为A
EXEC sp_rename 'tb.[b]', 'a', 'COLUMN'
goselect * from tbdrop table tb/*
a
---------------------
aaaaaa (所影响的行数为 1 行)
*/
--2005.
create table tb(a text)
insert into tb values ('aaaaaa')
goalter table tb alter column a char(255)
goselect * from tbdrop table tb/*
a
------------
aaaaaa
(1 行受影响)
*/-----------------------
--2000
create table tb(a text)
insert into tb values ('aaaaaa')
go--加个列B
alter table tb add b char(255)
go
--将B设置为A的值
update tb set b = cast(a as varchar)
go
--删除A
alter table tb drop column a
go
--更改列名B为A
EXEC sp_rename 'tb.[b]', 'a', 'COLUMN'
goselect * from tbdrop table tb/*
a
---------------------
aaaaaa (所影响的行数为 1 行)
*/
ALTER TABLE t_subprocessplan alter column processnumber SMALLIT