[Database] ADO Data Types與數據庫值對應

嘿！有這個對應表的話，用程式來建立資料表就方便多了。

由於用 asp + oldeb for foxpro，所以要參考 Oledb 的部分。

ADO Data Types與數據庫值對應 http://www.zaoxue.com/article/tech-48473.htm

DataType Enum	Value	Access	SQLServer
adBigInt	20		BigInt (SQL Server 2000 +)
adBinary	128		Binary TimeStamp
adBoolean	11	YesNo	Bit
adChar	129		Char
adCurrency	6	Currency	Money SmallMoney
adDate	7	Date	DateTime
adDBTimeStamp	135	DateTime (Access 97 (ODBC))	DateTime SmallDateTime
adDecimal	14
adDouble	5	Double	Float
adGUID	72	ReplicationID (Access 97 (OLEDB)), (Access 2000 (OLEDB))	UniqueIdentifier (SQL Server 7.0 +)
adIDispatch	9
adInteger	3	AutoNumber Integer Long	Identity (SQL Server 6.5) Int
adLongVarBinary	205	OLEObject	Image
adLongVarChar	201	Memo (Access 97) Hyperlink (Access 97)	Text
adLongVarWChar	203	Memo (Access 2000 (OLEDB)) Hyperlink (Access 2000 (OLEDB))	NText (SQL Server 7.0 +)
adNumeric	131	Decimal (Access 2000 (OLEDB))	Decimal Numeric
adSingle	4	Single	Real
adSmallInt	2	Integer	SmallInt
adUnsignedTinyInt	17	Byte	TinyInt
adVarBinary	204	ReplicationID (Access 97)	VarBinary
adVarChar	200	Text (Access 97)	VarChar
adVarWChar	202	Text (Access 2000 (OLEDB))	NVarChar (SQL Server 7.0 +)

[DATABASE] 各種資料庫的欄位型態

下列的參考資料十分不錯，列出大部分用到的資料庫欄位型態，寫程式時還蠻有用的！

Databases - Field Types http://mc-computing.com/Databases/FieldTypes.html

ex:

Foxpro

Type	Size	Description
Character	1 to 254
Currency	8 bytes	18 significant figures, including 4 decimal places Not available in Database Explorer
Date	8 bytes	January 1st, 1 A.D to December 31st, 9999 A.D
DateTime	8 bytes
Logical	1 byte
Variant		Can hold any type of field
Double	8 bytes	+/-4.94065645841247E-324 to +/-8.9884656743115E307 13 significant figures This range does not make sense
Numeric	1 to 20 bytes	- .9999999999E+19 to .9999999999E+20 up to 10 significant figures (specified by the user), same as Float
Float	1 to 20 bytes	- .9999999999E+19 to .9999999999E+20 up to 10 significant figures (specified by the user), same as Numeric
Integer	4 bytes	-2,147,483,647 to 2,147,483,647
Integer (Autoinc)	4 bytes	Autoincrement field
General	4 bytes in table	Reference to an OLE object The type is OLE in Database Explorer
Memo	4 bytes in table	Values may be modified depending on the language mapping Database Explorer indicates that these are actually 10 bytes each
Memo (Binary)	4 bytes in table	Values are not modified When the code page changes

[ADO] Foxpro

建立資料表(TABLE)
EX: Create Table test( id char(10), bookname character(100), number int)

刪除資料表
EX: DROP TABLE test

新增記錄
EX1: INSERT INTO test VALUES ('111', 'Life is Sad', 100)
EX2: INSERT INTO test (id, bookname, number) VALUES ('111', 'Life is Sad', 100)

• foxpro 8.0 以後可以用 autoinc 型態來設定自動編號


• oledb for vfp 支援 autoinc 語法,
  ex: Create Table test( id int primary key autoinc, bookname character(100), number int)


• oledb for vfp 不支援 " CREATE DATABASE" 的語法

轉貼 - REMBO 與 GHOST 之比較

Rembo 和 ghost 都是管理電腦教室的好幫手，兩者的管理方式其實有很大的差異，若是個人的話，比較偏愛用 Rembo 這種方式，不過，前提是網路和主機不能出問題啊！！

以下是台中縣吳仁智老師對兩者的比較：http://www.cses.tcc.edu.tw/~chihwu/rembo.htm

[HTML/CSS] 避免誤用不佳的 HTML標籤

開宗明義就講了，儘量用 CSS 來取代常用的HTML。
請詳讀 http://webdesign.about.com/od/css/a/aa101706.htm

How to Avoid Deprecated HTML

Use CSS Instead

When you're trying to write valid XHTML, you need to avoid the elements that have been deprecated. Using them will result in Web pages that may not work in a future version. This is because while the tag is still part of the XHTML specification, it may not be included in the future. And if it's not included, browsers won't support it.

Many deprecated XHTML elements were deprecated in favor of CSS style sheets. And it can be very easy to use CSS instead of many of these elements.

-------------------------------------------以下省略

[程式設計] 在文字方塊按下 Enter 後做動作

原本利用 Submit 按鈕時都沒有問題，不過，因為在表單送出前要先做檢查，所以把 submit 改成 button，這一來在文字方塊按 【Enter】就沒有作用了。

解決之道是利用 onKeyDown 這個事件來捕捉 【Enter】的 KeyCode，作法如下：
------------------------------------------------------------------------------------------
<script language=javascript>
function EnterToTab(){
if(event.keyCode==13)
event.keyCode=9;
}

</script>
------------------------------------------------------------------------------------------
在文字方塊中加入 onkeydown="EnterToTab();" 的屬性，這樣一來就可以了。

不過，這時又會出現新的問題，在 firefox 無法捕捉到 Enter 的 KeyCode，原來兩者的捕捉 KeyCode 的屬性不一樣，完整解決方式如下：

------------------------------------------------------------------------------------------
function EnterToSubmit(e){

var keynum;
if(window.event) { // IE
keynum = e.keyCode;
}else if(e.which) { // Netscape/Firefox/Opera
keynum = e.which;
}
if(keynum == 13){
document.forms["formName"].submit();
}

}
------------------------------------------------------------------------------------------
onKeyDown="EnterToSubmit(event);"

FTP 主動式與被動式

雖然是英文，不過還是很值得花點時間好好看看！

Active FTP vs. Passive FTP, a Definitive Explanation