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The cast to value type 'Int32' failed because the materialized value is null
...where there can be unexpected nulls in different places. ...DefaultIfEmpty(0).Sum(0) can help in this (quite simple) case, where there might be no elements and sql's SUM returns null whereas c# expect 0.
A more general approach is to use ?? which will be translated to COALESCE whenever there is a r...
Regular expression to allow spaces between words
...
tl;dr
Just add a space in your character class.
^[a-zA-Z0-9_ ]*$
Now, if you want to be strict...
The above isn't exactly correct. Due to the fact that * means zero or more, it would match all of the following cases that one would not usually mean to match:
An empty str...
Flexbox and Internet Explorer 11 (display:flex in ?)
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According to http://caniuse.com/#feat=flexbox:
"IE10 and IE11 default values for flex are 0 0 auto rather than 0 1 auto, as per the draft spec, as of September 2013"
So in plain words, if somewhere in your CSS you have something like this: flex:1 , that is not translated the...
Drop shadow for PNG image in CSS
...s for IE.
.shadowed {
-webkit-filter: drop-shadow(12px 12px 25px rgba(0,0,0,0.5));
filter: url(#drop-shadow);
-ms-filter: "progid:DXImageTransform.Microsoft.Dropshadow(OffX=12, OffY=12, Color='#444')";
filter: "progid:DXImageTransform.Microsoft.Dropshadow(OffX=12, OffY=12, Color='#4...
urllib2.HTTPError: HTTP Error 403: Forbidden
...atch/get_quote/getHistoricalData.jsp?symbol=JPASSOCIAT&fromDate=1-JAN-2012&toDate=1-AUG-2012&datePeriod=unselected&hiddDwnld=true"
hdr = {'User-Agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.64 Safari/537.11',
'Accept': 'text/h...
C# 'is' operator performance
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answered Mar 26 '09 at 16:09
Andrew HareAndrew Hare
310k6363 gold badges611611 silver badges614614 bronze badges
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Regular expression to limit number of characters to 10
...e a regular expression that will only allow lowercase letters and up to 10 characters. What I have so far looks like this:
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Set transparent background using ImageMagick and commandline prompt
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140
I am using ImageMagick 6.6.9-7 on Ubuntu 12.04.
What worked for me was the following:
convert t...
Return first match of Ruby regex
...Name[/regular expression/]. This is an example output from irb:
irb(main):003:0> names = "erik kalle johan anders erik kalle johan anders"
=> "erik kalle johan anders erik kalle johan anders"
irb(main):004:0> names[/kalle/]
=> "kalle"
...
What do 'real', 'user' and 'sys' mean in the output of time(1)?
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2130
Real, User and Sys process time statistics
One of these things is not like the other. Real ref...