判斷成績是否為NULL

IS NULL

判斷值是否為NULL


學號 成績
S0001 56
S0001 73
S0002 92
S0002 63
S0003 92
S0003 70
S0004 75
S0004 88
S0004 68
S0005 NULL

SELECT *
from  xx
where 成績 IS NULL


不可用    成績 = NULL

匯入資料庫-以TSQL方式

exec sp_attach_db '<<資料庫名稱>>','<<檔案路徑1>>','<<檔案路徑2>>'

ex:

exec sp_attach_db  ‘db_name’ , ’D:\ch4_DB.mdf’’,’D:\ch4_DB_log.ldf’

Visual Stdio 使用

將不知道的物件反白                按F1 可以連上MS的MSDN
DateTime

[WAMP]WampServer 修改預設開啟瀏覽器

更改  wampmanager.conf  和  wampmanager.ini


[wampmanager.conf ]
[main]
language = "chinese_trad"
status = offline
wampserverVersion = 2.4
wampserverLastKnown = 2.4
installDir = "g:/wamp2"
navigator = "C:\Program Files\Google\Chrome\Application\chrome.exe"
defaultLanguage = english

[wampmanager.ini]
[Menu.Left]
;WAMPMENULEFTSTART
Type: separator; Caption: "Powered by Alter Way"
Type: item; Caption: "Localhost"; Action: run; FileName: "C:\Program Files\Google\Chrome\Application\chrome.exe"; Parameters: "http://localhost/"; Glyph: 5
Type: item; Caption: "phpMyAdmin"; Action: run; FileName: "C:\Program Files\Google\Chrome\Application\chrome.exe"; Parameters: "http://localhost/phpmyadmin/"; Glyph: 5
Type: item; Caption: "www 目錄"; Action: shellexecute; FileName: "g:/wamp2/www"; Glyph: 2
Type: submenu; Caption: "Apache"; SubMenu: apacheMenu; Glyph: 3
Type: submenu; Caption: "PHP"; SubMenu: phpMenu; Glyph: 3
Type: submenu; Caption: "MySQL"; SubMenu: mysqlMenu; Glyph: 3
Type: separator; Caption: "Debug"
;Type: item; Caption: "Client XDebug"; Glyph: 6; Action: run; FileName: "g:/wamp2/tools/xdc/xdc.exe"
Type: item; Caption: "webGrind"; Action: run; FileName: "C:\Program Files\Google\Chrome\Application\chrome.exe"; Parameters: "http://localhost/webgrind/"; Glyph: 5
Type: separator; Caption: "Quick Admin"
;Type: servicesubmenu; Caption: "Apache"; Service: wampapache; SubMenu: apache

改成: C:\Program Files\Google\Chrome\Application\chrome.exe

[sql test]利用any

利用any從[訂購]資料表中,取出訂購產品是[豆沙包]類的訂單.



SELECT *
FROM 訂單
WHERE 產品編號 = any
(  select 產品編號 
   from 產品
   where 產品名稱 like '*豆沙包'


);

[test]sql

http://www.javaworld.com.tw/jute/post/view?bid=21&id=217814&tpg=9&ppg=1&sty=0&age=0

[mysql] How to create a IDENTITY column in MySQL?

create TABLE Table1
(
        ID int AUTO_INCREMENT  PRIMARY KEY,  
        classid int,
        sex varchar(10),
        age int
     
 )

ID 會自動加1且是PRIMARY KEY

AUTO_INCREMENT 相當於 IDENTITY (1,1)