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MySQL Query GROUP BY day / month / year
...in some cases such as where records span several years. SELECT COUNT(event_id), DATE_FORMAT(event_start, '%Y/%m')
– Ric
Apr 4 '13 at 10:25
...
Placeholder in UITextView
...property (nonatomic, retain) IBInspectable UIColor *placeholderColor;
-(void)textChanged:(NSNotification*)notification;
@end
UIPlaceHolderTextView.m:
#import "UIPlaceHolderTextView.h"
@interface UIPlaceHolderTextView ()
@property (nonatomic, retain) UILabel *placeHolderLabel;
@end
@implemen...
Virtual Memory Usage from Java under Linux, too much memory used
...
This has been a long-standing complaint with Java, but it's largely meaningless, and usually based on looking at the wrong information. The usual phrasing is something like "Hello World on Java takes 10 megabytes! Why does it need that?" Well, here's a way to make Hello World on a 64-bit JVM ...
【精心整理】【实用】visual C++中最常用的类与API函数 - C/C++ - 清泛网 -...
...个CArchive对象
CArchive(CFile* pFile,UINT nMode,int nBufSize=4096,void* lpBuf=NULL);
参数：pFile 指向CFile对象的指针，这个CFile对象是数据的最终源或目的；
nMode是标志，取值为CArchive::load时，从文档中加载数据（要求CFile读许可），取值为CArch...
How do I create a custom iOS view class and instantiate multiple copies of it (in IB)?
...t you can construct your interface in IB using a .xib file which is nearly identical to using the storyboard version; You should even be able to copy & paste your views as a whole from your existing interface to the .xib file.
To test this out I created a new empty .xib named "MyCustomTimerView...
What happens if you call erase() on a map element while iterating from begin to end?
...;
while(pm_it != port_map.end())
{
if (pm_it->second == delete_this_id)
{
pm_it = port_map.erase(pm_it);
}
else
{
++pm_it;
}
}
C++03
Erasing elements in a map does not invalidate any iterators.
(apart from iterators on the element that was deleted)
Actu...
Comparing strings with == which are declared final in Java
...erwise, always prefer String.equals(String) for String comparison.
So it means if you call String.intern() you can compare two strings using == operator. But here String.intern() is not necessary because in Java final String are internally interned.
You can find more information String comparisio...
delete_all vs destroy_all?
...ach to delete records from a table. For instance, I have a user whose user ID is across many tables. I want to delete this user and every record that has his ID in all tables.
...
How to change the Text color of Menu item in Android?
Can I change the background color of a Menu item in Android?
27 Answers
27
...
Table header to stay fixed at the top when user scrolls it out of view with jQuery
...ixed position to show the header at the top of the page.
HTML:
<table id="header-fixed"></table>
CSS:
#header-fixed {
position: fixed;
top: 0px; display:none;
background-color:white;
}
JavaScript:
var tableOffset = $("#table-1").offset().top;
var $header = $("#table-1...