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Óŵã:ËãµÃÉÏÊÇÕæÕýµÄÎÞÏÞ·ÖÀ࣬²»¹ýParentPathÊÇÓоÖÏÞÐÔ,ClassIDÊDZêʶÁÐ×Ô¶¯ÔöÒ».
ȱµã:ÐÂÔö¹ý³ÌÖÐParentID²»´æÔÚ»¹Ã»ÓÐÍêÉÆ£¬»á²åÈëNULLÊý¾Ý.ºóÃæÈý¸ö´æ´¢¹ý³Ì»¹ÔÚ²âÊÔ¡£
if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[ArticleClass]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
drop table [dbo].[ArticleClass]
GO
CREATE TABLE [dbo].[ArticleClass] (
[ClassID] [int] IDENTITY (1, 1) NOT NULL ,
[ClassName] [nvarchar] (100) COLLATE Chinese_Taiwan_Stroke_CI_AS NULL ,
[ParentID] [int] NULL ,
[ParentPath] [nvarchar] (255) COLLATE Chinese_Taiwan_Stroke_CI_AS NULL ,
[Depth] [int] NULL ,
[RootID] [int] NULL ,
[Child] [int] NULL ,
[PrevID] [int] NULL ,
[NextID] [int] NULL ,
[OrderID] [int] NULL
) ON [PRIMARY]
GO
ALTER TABLE [dbo].[ArticleClass] ADD
CONSTRAINT [DF_ArticleClass_ParentID_65E11278] DEFAULT (0) FOR [ParentID],
CONSTRAINT [DF_ArticleClass_Depth_66D536B1] DEFAULT (0) FOR [Depth],
CONSTRAINT [DF_ArticleClass_RootID_67C95AEA] DEFAULT (0) FOR [RootID],
CONSTRAINT [DF_ArticleClass_Child_68BD7F23] DEFAULT (0) FOR [Child],
CONSTRAINT [DF_ArticleClass_PrevID_69B1A35C] DEFAULT (0) FOR [PrevID],
CONSTRAINT [DF_ArticleClass_NextID_6AA5C795] DEFAULT (0) FOR [NextID],
CONSTRAINT [DF_ArticleClass_OrderID_6B99EBCE] DEFAULT (0) FOR [OrderID],
CONSTRAINT [PK_ArticleClass] PRIMARY KEY CLUSTERED
(
[ClassID]
) ON [PRIMARY]
GO
exec sp_addextendedproperty N'MS_Description', N'Ö÷¼ü', N'user', N'dbo', N'table', N'ArticleClass', N'column', N'ClassID'
GO
exec sp_addextendedproperty N'MS_Description', N'Àà±ðÃû³Æ', N'user', N'dbo', N'table', N'ArticleClass', N'column', N'ClassName'
GO
exec sp_addextendedproperty N'MS_Description', N'¸¸ÀàID', N'user', N'dbo', N'table', N'ArticleClass', N'column', N'ParentID'
GO
exec sp_addextendedproperty N'MS_Description', N'¸¸Àà·¾¶', N'user',
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DROP TABLE --´ÓÊý¾Ý¿âÖÐɾ³ý±í
ALTER TABLE --ÐÞ¸ÄÊý¾Ý¿â±í½á¹¹
CREATE VIEW --´´½¨Ò»¸öÊÓͼ
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³£¼ûµÄÎÊÌâÀàÐÍ£º¸ù ......
--¾ÛºÏº¯Êý
use pubs
go
select avg(distinct price) --ËãÆ½¾ùÊý
from titles
where type='business'
go
use pubs
go
select max(ytd_sales) --×î´óÊý
from titles
go
use pubs
go
select min(ytd_sales) --×îÐ¡Ê ......
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SQL round()Ïê½â
roundÓÐÁ½¸öÖØÔØ,Ò»¸öÓдøÓÐÁ½¸ö²ÎÊýµÄ,Ò»¸öÊÇ´øÓÐÈý¸ö²ÎÊýµÄ,
ÿһ¸ö²ÎÊý¶¼ÏàͬÊÇÒª´¦ÀíµÄÊý,
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select round(748.585929,-1) 750.000000
select round(748.58592 ......
sqlȨÏÞ:
´´½¨User:
insert into mysql.user(Host,User,Password)
values("localhost","cordev",password("xasoftorg"));
insert into
mysql.user(Host,User,Password)
values("localhost","corhotfix",password("xasoftorg"));
insert into
mysq ......