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How do I check if a column is empty or null in MySQL?
...= ' ' IS TRUE
'' = ' ' IS TRUE
' ' = ' ' IS TRUE
' ' = ' ' IS TRUE
etc
Therefore, this should work regardless of how many spaces make up the some_col value:
SELECT *
FROM T
WHERE some_col IS NULL
OR some_col = ' ';
or more succinctly:
SELECT *
FROM T
WHERE NULLIF(some_c...
Java equivalent to C# extension methods
...no limitations and does not suffer from issues with generics, lambdas, IDE etc. Manifold provides several other features such as F#-style custom types, TypeScript-style structural interfaces, and Javascript-style expando types.
Additionally, IntelliJ provides comprehensive support for Manifold via...
How to get GET (query string) variables in Express.js on Node.js?
...riables in the query string in Node.js just like we get them in $_GET in PHP?
26 Answers
...
Inline functions vs Preprocessor macros
...Because the compiler will not inline if doing so will generate slower code etc. The compiler does a lot of analysis that the Engineer can not and does the correct thing.
– Martin York
Jul 16 '09 at 16:20
...
Pretty graphs and charts in Python [closed]
...ackends for Tk, Qt, Wx, Cocoa, and many image types such as PDF, EPS, PNG, etc.). The main advantages of Chaco are its speed relative to Matplotlib and its integration with Enthought's Traits API for interactive applications.
...
Equivalent of String.format in jQuery
...ax of the popular .net methods, e.g. String.format(), String.startsWith(), etc. Are there equivalents to them in jQuery?
20...
Why is Node.js single threaded? [closed]
...b servers typically do ALOT of cpu intensive stuff it's not JUST database fetching. We need to process what we fetch, and do alot of business logic alot of the time before serving it up to the client.
– foreyez
Jul 31 '13 at 0:40
...
控件重绘函数/消息OnPaint,OnDraw,OnDrawItem,DrawItem的区别 - C/C++ - 清...
...时对控件的绘制，上面介绍的差不多了，还有一个CView的问题，也就是OnPaint和Ondraw的关系，其实这个很简单，CView::OnPaint()的源码如下：
void CView::OnPaint()
{
CPaintDC dc(this);
OnPrepareDC(&dc);
OnDraw(&dc)
}
...
submitting a GET form with query string params and hidden params disappear
...ntains the target, where the form should be processed? like: action="index.php?site=search". I'm not sure, if putting the GET parameter in hidden input fields is an god idea.
– The Bndr
Aug 24 '17 at 13:09
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How to submit a form with JavaScript by clicking a link?
... works well without any special function needed. Much easier to write with php as well. <input onclick="this.form.submit()"/>
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