create table a(name varchar(10),id int default 0) insert into a(name) select 'a' union select 'b' union select 'c' union select 'd' union select 'e'select * from a drop table a ---- name id a 0 b 0 c 0 d 0 e 0
ALTER TABLE tablename ADD 列名 int DEFAULT 0
现有的数据 update 一下
用update当然行,如果不用update呢?直接在添加列的时候完成这个操作!
ALTER TABLE tablename ADD 列名 int not null DEFAULT 0 ALTER TABLE tablename ADD 列名 int DEFAULT 0
报歉,第二句写的有点问题 alter table tablename alter 列名 int default 0
应该这样写 ALTER TABLE dbo.TableName ADD ColumnName int CONSTRAINT AddDateDflt default(0) WITH values这样,在你插入了新列后,表中原有数据的该列的值就是新列的默认值了可以结贴了
create table a(name varchar(10),id int default 0) insert into a(name) select 'a' union select 'b' union select 'c' union select 'd' union select 'e' insert into a values('f',2) insert into a(name) values('h') go select * from a ---- name id a 0 b 0 c 0 d 0 e 0 f 2 h 0
insert into a(name)
select 'a'
union select 'b'
union select 'c'
union select 'd'
union select 'e'select * from a
drop table a
----
name id
a 0
b 0
c 0
d 0
e 0
update 一下
ALTER TABLE tablename ADD 列名 int DEFAULT 0
alter table tablename alter 列名 int default 0
ALTER TABLE dbo.TableName ADD ColumnName int CONSTRAINT AddDateDflt default(0) WITH values这样,在你插入了新列后,表中原有数据的该列的值就是新列的默认值了可以结贴了
insert into a(name)
select 'a'
union select 'b'
union select 'c'
union select 'd'
union select 'e'
insert into a values('f',2)
insert into a(name) values('h')
go
select * from a
----
name id
a 0
b 0
c 0
d 0
e 0
f 2
h 0