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How do you query for “is not null” in Mongo?
...
db.collection_name.find({"filed_name":{$exists:true}});
fetch documents that contain this filed_name even it is null.
My proposition:
db.collection_name.find({"field_name":{$type:2}}) //type:2 == String
You can check on the required...
How to get unique device hardware id in Android? [duplicate]
... the link below
http://android-developers.blogspot.in/2011/03/identifying-app-installations.html
ANDROID_ID
import android.provider.Settings.Secure;
private String android_id = Secure.getString(getContext().getContentResolver(),
Secure.ANDROID_...
How can I listen for a click-and-hold in jQuery?
...tartTrigger(e) {
var $elem = $(this);
$elem.data('mouseheld_timeout', setTimeout(function() {
$elem.trigger('mouseheld');
}, e.data));
}
function stopTrigger() {
var $elem = $(this);
clearTimeout($elem.data('mouseheld_timeout'));
}
...
Git Bash is extremely slow on Windows 7 x64
...
Problem is with $(__git_ps1) ... removing this makes everything superfast
– Hendy Irawan
Apr 7 '15 at 3:27
...
Is it worth using Python's re.compile?
...e.py (comments are mine):
def match(pattern, string, flags=0):
return _compile(pattern, flags).match(string)
def _compile(*key):
# Does cache check at top of function
cachekey = (type(key[0]),) + key
p = _cache.get(cachekey)
if p is not None: return p
# ...
# Does act...
Understanding slice notation
...asic sequences don't support them.
>>> class slicee:
... def __getitem__(self, item):
... return repr(item)
...
>>> slicee()[0, 1:2, ::5, ...]
'(0, slice(1, 2, None), slice(None, None, 5), Ellipsis)'
...
Add Text on Image using PIL
...m PIL import ImageFont
from PIL import ImageDraw
img = Image.open("sample_in.jpg")
draw = ImageDraw.Draw(img)
# font = ImageFont.truetype(<font-file>, <font-size>)
font = ImageFont.truetype("sans-serif.ttf", 16)
# draw.text((x, y),"Sample Text",(r,g,b))
draw.text((0, 0),"Sample Text",(...
Implement touch using Python?
...is will create a file.txt at the path.
--
Path.touch(mode=0o777, exist_ok=True)
Create a file at this given path. If mode is given, it is combined with the process’ umask value to determine the file mode and access flags. If the file already exists, the function succeeds if exist_ok is t...
Exploitable PHP functions
...ese function calls are classified as Sinks. When a tainted variable (like $_REQUEST) is passed to a sink function, then you have a vulnerability. Programs like RATS and RIPS use grep like functionality to identify all sinks in an application. This means that programmers should take extra care when...
What's the difference between console.dir and console.log?
...ole.dir([1,2,3])
* Array[3]
0: 1
1: 2
2: 3
length: 3
* __proto__: Array[0]
concat: function concat() { [native code] }
constructor: function Array() { [native code] }
entries: function entries() { [native code] }
...
DOM objects also exhibit diff...