貧窮不能等，因為時間久了，你就會貧窮習慣了；
夢想不能等，因為努力晚了，人老就無能為力了；
學習不能等，因為懂得少了，就沒本事夢想成真了；
健康不能等，因為身體垮了，人生的一切就都沒了。
最近因為接手維護 & 開發舊的系統, 所以必須熟悉 前人寫的 SQL語法, 前輩習慣使用一串SQL語法,把所有的資料撈出來 ,這樣節省很多時間 ,速度也會快很多.
但是, 對於維護的人來說 ,剛開始真是痛苦啊 ...其中, 使用很多的 LEFT JOIN 合併資料, 我覺得很方便 ,但是不熟悉 會搞錯, 所以慢慢的會把相關的心得整理
作為資料參考備忘 放在這裡 ,歡迎交流討論喔 !!
以下，是國外論壇的一篇發問, 關於如何使用兩個以上的 LEFT JOIN ..
The inefficiency of the IN clause in SQL statement is well known. Could anyone suggest some workarounds for the following case.
在網路上找到的詳細介紹可拍101的好點,請參考
象山步道拍攝景點介紹
http://beb.anyday.com.tw/scenic_spots/01/index.php#item1
當一段 SQL 寫成如下:
update TABLE1 set Fields1 = ((select Fields1 from TABLE1 where Fields2 = (select Fields3 from TABLE2 where Fields2=ID )) + NUM) where Fields2 = (select Fields3 from TABLE2 where Fields2 = ID)
被執行時, 在 MySQL 會回應
You can't specify target table 'table name' for update in FROM clause .
解決方式:
CONVERT_TZ() 將時間日期值dt 從from_tz 給出的時區轉到to_tz給出的時區，然後返回結果值。
關於可能指定的時區的詳細論述。若引數無效，則這個函數會返回 NULL。
在從若from_tz 到UTC的轉化過程中，該值超出 TIMESTAMP 類型的被支持範圍，那麼轉化不會發生。關於 TIMESTAMP 範圍的論述。
mysql> SELECT CONVERT_TZ('2004-01-01 12:00:00','GMT','MET');
-> '2004-01-01 13:00:00'
哈..
First off, you will need to have Apache and MySQL installed. You can download Apache at http://www.apache.org/dist/. For information on installing Apache, see Joey's Apache Guide. Once Apache is set up, you will need MySQL installed and running. You can download the MySQL source from http://www.mysql.com and for information on installing and setting up MySQL, you can read DJG's MySQL Guide.
After that, you need to retrieve the source for the mod_auth_mysql source.
Place the source into your apache tree in the libexec directory. Mine is located at
/usr/local/apache/libexec/
某些情況, 可能會把 時區 變更 ,一般是透過 Linux 的 Setup 去調整時區 ,
除了那個方式以外 ,直接複製
/usr/share/zoneinfo/Asia/Taipei (或其它時區的檔案)
當數字不足時, 通常會想到用 sprintf("%02d",$xxx); 去做補零的動作, 但是, 其實, 可以使用 php 的str_pad() 函式來解決這個需求 ,請參考以下的內容,謝謝
會找到有些使用sprintf函式的方法 像下面這樣
1.$var = 1;2.echo sprintf("%02d", $var);Description:
When you create a trigger without specifying the BEGIN/END mysqldump will not dump correctly.
How to repeat:
Step 1
「2009台灣寬頻通訊展」在經濟部貿易局與工業局的支持指導下，由外貿協會、台灣區電機電子同業公會共同主辦，WiMAX Forum、工研院、資策會與台北市電腦商業同業公會協辦。除將擴大展覽規模，結合同檔期國際大型會議包括「WiMAX Forum Member Conference Taipei, Taiwan 」、「WiMAX Summit Taiwan 2009」、「Broadband Forum Taiwan, 2009」以及「IPTV Develop Forum 2009 - IPTV on Multi-Platforms」。
別急著轉台 Orz .... 內有正妹喔 !!
Subversion, or SVN, is a versioning control system used to maintain current and historical versions of files. I decided to start using SVN because I do development on more than one computer and SVN will allow me to have one central repository with all of my project files. The server I am using is a standard desktop computer running Fedora Core 10.
Install Apache
The first step is to install Apache2 and the WebDAV SVN module. This can be done by running the commands:
# yum install httpd
轉述 Softonic - Cyril Roger 對於 Flashget 的推薦內容.
Here at Softonic we download and test many programs each day, so having a download manager on our PCs definitely makes our life easier. Flashget is considered by many to be the best download manager out there, but does it really deserve this reputation? We gave it a test drive to uncover the features that make it such a widely-coveted application.
Flashget takes charge of your downloads, automating the whole process from start to finish. Among the essential features of a download manager is batch downloading of multiple files, well handled by the program. Flashget also lets you schedule downloads to start at particular times. This is good when you have a long list of files waiting to be downloaded but you want to avoid sucking up bandwidth. You can schedule them to download one after the other, or at times when you will not be using your PC. What makes Flashget a particularly valuable tool is the speed of its downloads. You can cut up a file into various parts to download it faster and can optimize the speed according to your connection. When tested out, Flashget definitely revealed higher performances than the in-browser download managers included in Internet Explorer and Firefox.
Modem users will appreciate the auto-connect/disconnect function but the majority of users, who are on broadband, can ignore this feature. Our favourite function was the ability to explore a website for all possible downloads, an easy way to catch all the files in a site in one go. However, avoid using this tool for a website like Softonic, otherwise you’ll end up with hundreds or even thousands of random programs queued up.
Banana-Pi, 樹梅派應用 
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