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select name from syscolumns where id in (select id from sysobjects where type = 'u' and name = 'ÏàÓ¦±íÃû')
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if exists (select * from dbo.sysobjects where id = object_id(N'[dbo].[tb_cost]') and OBJECTPROPERTY(id, N'IsUserTable') = 1)
drop table [dbo].[tb_cost]
GO
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CREATE TABLE [dbo].[tb_cost] (
[id] [int] IDENTITY (1, 1) NOT NULL ,
[inputtime] [datetime] NOT NULL ,
[pushcount] [int] NOT NULL ,
[revertcount] [int] NOT NULL ,
[revertrate] [varchar] (50) COLLATE Chinese_PRC_CI_AS NOT NULL ,
[unitprice] [float] NOT NULL ,
[cost] [float] NOT NULL ,
[income] [float] NOT NULL ,
[rate] [varchar] (50) COLLATE Chinese_PRC_CI_AS NOT NULL ,
[pushinfor] [varchar] (8000) COLLATE Chinese_PRC_CI_AS NOT NULL
) ON [PRIMARY]
GO
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create clustered index Ë÷ÒýÃû on ±íÃû(±í.×Ö¶Î)
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alter table ±íÃû add fa int not null default 0
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sql="select top 6 * from table where (id not in (select top 4 id from table order by id desc)) order by id desc"
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sql="select top m-n+1 * from table where (id not in (select top n-1 id from table))
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DML—Êý¾Ý²Ù×ÝÓïÑÔ(SELECT£¬DELETE£¬UPDATE£¬INSERT)
DCL—Êý¾Ý¿ØÖÆÓïÑÔ(GRANT£¬REVOKE£¬COMMIT£¬ROLLBACK)
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CREATE DATABASE database-name
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S:select abs(-1) value
O:select abs(-1) value from dual
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S:select ceiling(-1.001) value
O:select ceil(-1.001) value from dual
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S:select floor(-1.001) value
O:select floor(-1.001) value from dual
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S:select cast(-1.002 as int) v ......
alter table ±íÃû
add constraint Ô¼ÊøÃû
foreign key(×Ö¶ÎÃû) references Ö÷±íÃû(×Ö¶ÎÃû)
on delete cascade
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Foreign Key
(column[,...n])
references referenced_table_name[(ref_column[,...n])]
[on delete cascade]
[on update cascade]
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column:ÁÐÃû
referenced_table_name:Íâ¼ü²Î¿¼µÄÖ÷¼ü± ......
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import java.io.*;
import jxl.*;
public class ExcelToSql {
public static void main(String args[])
{
try
{
Workbook book= Workbook.getWorkbook(new File("D:\\workspaceuse6\\foundation\\test\\com\\gres ......