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quick random row selection in Postgres
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You might want to experiment with OFFSET, as in
SELECT myid FROM mytable OFFSET floor(random()*N) LIMIT 1;
The N is the number of rows in mytable. You may need to first do a SELECT COUNT(*) to figure out the value of N.
Update (by Antony Hatchkins)
You must use floor here:
SELE...
jQuery checkbox checked state changed event
I want an event to fire client side when a checkbox is checked / unchecked:
10 Answers
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Horizontal ListView in Android?
...lected item at the same spot I clicked. How can I rectify this problem? My idea was to set the ListView with a horizontal scroll. Share your idea?
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When should I use h:outputLink instead of h:commandLink?
... renders a HTML <a> element with an onclick script which submits a (hidden) POST form and can invoke a managed bean action method. It's also required to be placed inside a <h:form>.
<h:form>
<h:commandLink value="link text" action="destination" />
</h:form>
The ?fa...
How to override the copy/deepcopy operations for a Python object?
...her copy nor deepcopy call the constructor of the object being copied. Consider this example. class Test1(object): def init__(self): print "%s.%s" % (self.__class.__name__, "init") class Test2(Test1): def __copy__(self): new = type(self)() return new t1 = Test1() co...
Why are dashes preferred for CSS selectors / HTML attributes?
In the past I've always used underscores for defining class and id attributes in HTML. Over the last few years I changed over to dashes, mostly to align myself with the trend in the community , not necessarily because it made sense to me.
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Use Font Awesome Icon in Placeholder
...lass="form-group">
<input type="text" class="form-control empty" id="iconified" placeholder="&#xF002;"/>
</div>
</form>
With this CSS:
input.empty {
font-family: FontAwesome;
font-style: normal;
font-weight: normal;
text-decoration: inherit;
}
And ...
Random string generation with upper case letters and digits
...e:
>>> import string
>>> import random
>>> def id_generator(size=6, chars=string.ascii_uppercase + string.digits):
... return ''.join(random.choice(chars) for _ in range(size))
...
>>> id_generator()
'G5G74W'
>>> id_generator(3, "6793YUIO")
'Y3U'
Ho...
json_encode is returning NULL?
...as having the same problem here. I had values with non-utf8 chars like "Validação de Formulários". I know this question is a little bit old now, but that's the awesomeness of internet!!
– fabio
Feb 11 '11 at 23:23
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Using CSS :before and :after pseudo-elements with inline CSS?
... they're defined on, and not to any pseudo-elements it generates.
As an aside, the main difference between pseudo-elements and pseudo-classes in this aspect is that properties that are inherited by default will be inherited by :before and :after from the generating element, whereas pseudo-class sty...