if exists (select 1 from sysobjects where type='u' and name =tablename)
begin
alter table tablename add columnname columntype
end
else
begin
create table tablename (col1 int identity(1,1)...)
end
begin
alter table tablename add columnname columntype
end
else
begin
create table tablename (col1 int identity(1,1)...)
end
begin
create table 表名(ID int identity(1,1),....)
end
else
begin
alter table 表名 add 字段1 类型1,字段2 类型2....
end
begin
alter table tablename add 字段1 类型1,字段2 类型2....
end
else
begin
create table tablename (col1 int identity(1,1)...)
end