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Is there any difference between GROUP BY and DISTINCT
... 12 there do appear to be cases where DISTINCT, getting distinct values by UNION, and GROUP BY work differently. I just had a case earlier today where DISTINCT and distinct by UNION cause an oracle error, but GROUP BY worked; I was selecting only 1 column from a view and not using any aggregation; I...
What is 'Pattern Matching' in functional languages?
...e functional languages allow you define simple data types called "disjoint unions" or "algebraic data types". These data structures are simple containers, and can be recursively defined. For example:
type 'a list =
| Nil
| Cons of 'a * 'a list
defines a stack-like data structure. Think of...
技术人员如何创业《三》- 合伙人的分工 - 资讯 - 清泛网 - 专注C/C++及内核技术
技术人员如何创业《三》- 合伙人的分工中国梦我们习主席上台后就大大倡导。国家领导人有他们的中国梦，创业者也怀揣着创业的梦想。我们张罗好产品就要准备风风火火的大干一番了。 “中国梦”我们习主席上台后就大大...
如何跟程序员谈一场没有Bug的恋爱 - 杂谈 - 清泛网 - 专注C/C++及内核技术
如何跟程序员谈一场没有Bug的恋爱现在越来越多的妹子把恋爱目标锁定在程序员上，原因无他：呆萌又多金。但如何和程序员相处一直是个问题，这篇文章就教你如何优（xin）雅（j 现在越来越多的妹子把恋爱目标锁定在程序...
How to host a Node.Js application in shared hosting [closed]
... 30 minutes to set up the configuration, and it'll work with npm, Express, MySQL, etc.
See a2hosting.com.
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How to use NULL or empty string in SQL
...ERE SomeCol = '' OR SomeCol IS NULL;
SELECT *
FROM #T
WHERE SomeCol = ''
UNION ALL
SELECT *
FROM #T
WHERE SomeCol IS NULL;
SELECT *
FROM #T
WHERE EXISTS ((SELECT NULL UNION SELECT '') INTERSECT SELECT SomeCol);
And some non-sargable ones...
SELECT *
FROM #T
WHERE IIF(SomeCol <> '',0,1) ...
C/C++ Struct vs Class
...long ago, back when C++ was still known as "C with Classes."
Note that C unions work with C++, but not the other way around. For example
union WorksWithCppOnly{
WorksWithCppOnly():a(0){}
friend class FloatAccessor;
int a;
private:
float b;
};
And likewise
typedef union friend{...
App Inventor 2 如何接入ChatGPT：国内访问OpenAI的最佳方式 · App Inventor 2 中文网
...索
App Inventor 2 如何接入ChatGPT：国内访问OpenAI的最佳方式
如何接入OpenAI
通过token（访问令牌）接入
通过ApiKey接入
« 返回首页
如何接入OpenAI
由于...
App Inventor 2 计时器（Clock）详细用法示例 · App Inventor 2 中文网
...返回的当前时刻格式化成文本：
24小时格式怎么写？
如何定时一小时？
如何定点执行，比如到20:23分执行？
如何实现多个定时任务？
关闭屏幕时，如何让计时器继续工作？
« 返回首页
计时器在界面设计中的...
NSIS学习笔记（持续更新） - C/C++ - 清泛网 - 专注C/C++及内核技术
NSIS学习笔记（持续更新）Q 如何使用C++开发插件,示例环境：VS2013Update4参考资料[3]来做S1:新建一个空的C++DLL项目，nsMessageBoxPlugin.S2:复制C: Program File...Q 如何使用C++开发插件,示例
环境：VS2013Update4
参考资料[3]来做
S1:新建一个空...