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add column to mysql table if it does not exist
... number.
Another solution would be to just try the ALTER TABLE ADD COLUMN command. It should throw an error if the column already exists.
ERROR 1060 (42S21): Duplicate column name 'newcolumnname'
Catch the error and disregard it in your upgrade script.
...
Best way to store password in database [closed]
...ssword, you hash the value (using the same hashing algorithm and salt) and compare it to the hashed value in the database.
So, while it is a good thing you are thinking about this and it is a good question, this is actually a duplicate of these questions (at least):
How to best store user informa...
Installing multiple instances of the same windows service on a server
...a to our client application and everything is going great. The client has come up with a fun configuration request that requires two instances of this service running on the same server and configured to point at separate databases.
...
How do I add a simple jQuery script to WordPress?
... edited Apr 13 '17 at 12:37
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answered Aug 19 '12 at 9:23
kdevkdev
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Deep Learning（深度学习）学习笔记整理系列之（三） - 大数据 & AI - 清泛...
..._Series_3Deep Learning（深度学习）学习笔记整理系列zouxy09@qq.comhttp: blog.csdn.net zouxy09作者：Zouxyversion 1.0 2013-04-08原文网址：h...Deep Learning（深度学习）学习笔记整理系列
zouxy09@qq.com
http://blog.csdn.net/zouxy09
作者：Zouxy
version 1.0 2013-04-...
Is there any reason for using WebGL instead of 2D Canvas for 2D games/apps?
...these skills are harder to find, production is slower (due to the size and complexity of such a code base), and therefore it costs more.
WebGL is faster and it has more capabilities. No doubt about that. It's a native 3D API that gives you full access to the rendering pipeline, code and effects are...
How to count certain elements in array?
...s most elegant. E.g. for me, making a function call per element to just to compare it to a value is not elegant.
– Felix Kling
May 25 '11 at 8:33
...
.NET obfuscation tools/strategy [closed]
My product has several components: ASP.NET, Windows Forms App and Windows Service. 95% or so of the code is written in VB.NET.
...
Hibernate Criteria returns children multiple times with FetchType.EAGER
... SQL and how OUTER JOINs work
in SQL. If you do not fully understand and comprehend outer joins in
SQL, do not continue reading this FAQ item but consult a SQL manual or
tutorial. Otherwise you will not understand the following explanation
and you will complain about this behavior on the Hib...
C＋＋模板的特化 - C/C++ - 清泛网 - 专注C/C++及内核技术
...那么彻底
首先推荐两个不错的网址：
http://www.cnblogs.com/cutepig/archive/2009/02/12/1389479.html
http://read.newbooks.com.cn/info/175115.html
先说类模板的特化吧：
谁都没的说的全特化：
// general version
template<class T>
class Compare
{
public:...