我想在mysql中用触发器修改主键ID 的值

[你的数据库]

go

create

trigger

name

on

[table]

after

delete

as

begin

--定义游标，使你逐个往下找个ID，并执行update修改

declare

@flag

int

select

@flag=ID

from

deleted

declare

[cursorname]

cursor

for

select

ID

from

[table]

where

ID>@flag

open

[cursorname]

fetch

next

from

[cursorname]

update

[table]

set

ID=ID+1

where

ID=fetch

next

from

[cursorname]

WHILE

@@FETCH_STATUS

=

0

begin

update

[table]

set

ID=ID+1

where

ID=fetch

next

from

[cursorname]

close

[cursorname]

DEALLOCATE

authors_cursor

end

end

alter

table

表名

drop

constraint

主键名

修改主键：

alter

table

表名

add

constraint

主键名

primary

key

(column1,column2,....,column)

alter

table

t1

drop

column

c1

alter

table

t1

add

column

c1int

identity