SQL基础2

--输出字符串"I love you "对应的ASCII值和字符
declare @pos smallint, --位置
        @string varchar(10) --字符串
set @pos = 1;
set @string = 'I love you'

--datalength是一个全局数据，返回数据的长度
while (@pos <= datalength(@string))
begin 
    select ascii(substring(@string, @pos, 1)) as AsciiCode,   --获取ASCII码
           char(ascii(substring(@string, @pos, 1))) as ascchar--获取对应的字符
    set @pos = @pos + 1
end

create database studentInfo
on primary
( name = stu_data,
  filename = 'd:\stu_data.mdf',
  size = 3,
  maxsize = 15,
  filegrowth = 1)
log on
(
  name = stu_log,
  filename = 'd:\stu_log.ldf',
  size = 1,
  maxsize = 12,
  filegrowth = 10%
)

use student
go
create proc tea_pro
(@no char(6), @name nvarchar(8), @sex nchar(1), @age int, @title nchar(5), @tel varchar(12)
, @salary decimal(7), @num char(10))
as
 insert into teacher_info values(@no, @name, @sex, @age, @title, @tel, @salary, @num)
go

use student
go
create proc stud_proc
    (@startdate datetime, @enddate datetime, @recordcount int output) --用output指定为返回值
as
    if (@startdate is null or @enddate is null)
    begin
        raiserror('Null value are invalid!', 5, 5)
        return
    end
    select * from stud_info
    where birthday between @startdate and @enddate
    select @recordcount = @@rowcount
go