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How can I select rows with most recent timestamp for each key value?
...ensorID, timestamp;
Pretty self-explaining I think, but here's more info if you wish, as well as other examples. It's from the MySQL manual, but above query works with every RDBMS (implementing the sql'92 standard).
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How to define two fields “unique” as couple
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How would you handle this say if volume_number could be null? Mysql won't seem to enforce unique in that case.
– Greg
Jun 27 '11 at 17:28
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how to get an uri of an image resource in android
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@LucioCrusca - maybe you should specify the intent type - is it jpeg or png image?
– Axarydax
Feb 26 '14 at 11:19
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no new variables on left side of :=
... to a simple assignment statement := -> = or you can use a new variable if that's ok with your algorithm.
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JavaScript Date Object Comparison
...her. Coerce them to number:
alert( +startDate2 == +startDate3 ); // true
If you want a more explicity conversion to number, use either:
alert( startDate2.getTime() == startDate3.getTime() ); // true
or
alert( Number(startDate2) == Number(startDate3) ); // true
Oh, a reference to the spec: §11...
Load and execution sequence of a web page?
...oo much about the load and execution sequence of an ordinary web page. But now I need to know detail. It's hard to find answers from Google or SO, so I created this question.
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Rails 4 - passing variable to partial
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You need the full render partial syntax if you are passing locals
<%= render @users, :locals => {:size => 30} %>
Becomes
<%= render :partial => 'users', :collection => @users, :locals => {:size => 30} %>
Or to use the new hash sy...
Check if key exists and iterate the JSON array using Python
...id_7"}"""
def getTargetIds(jsonData):
data = json.loads(jsonData)
if 'to' not in data:
raise ValueError("No target in given data")
if 'data' not in data['to']:
raise ValueError("No data for target")
for dest in data['to']['data']:
if 'id' not in dest:
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Read logcat programmatically within application
...ode above.
The "-d" flag instruct to logcat to show log content and exit. If you remove the flag, logcat will not terminate and keeps sending any new line added to it.
Just have in mind that this may block your application if not correctly designed.
good luck.
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What is an .axd file?
...ptResource.AXD - instead it will be merely passed as the .js file you send if you reference a external script file. If you embed it in code then it may merely appear as part of the html as a tag and code but depending if you code according to how the ToolKit handles it - may or may not appear as as...