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How do I create a variable number of variables?
... answered Sep 3 '09 at 12:41
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difference between primary key and unique key
...d on multiple columns, e.g. Primary key (CustomerID, ProductID). This is called composite primary key. This is to clarify the first point, as it might be take as it is (read one key => one column ) by new comer to sql : )
– ken
Apr 10 '14 at 13:53
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Fixing JavaScript Array functions in Internet Explorer (indexOf, forEach, etc.) [closed]
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Many use the MDC fallback implementations (eg. for indexOf). They're generally rigorously standards-compliant, even to the extent of explicitly checking the types of all the arguments.
Unfortunately whilst it is clear that the authors regard ...
How to close activity and go back to previous activity in android
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I think you are calling finish() method in MainActivity before starting SettingsActivity.
The scenario which you have described will occur in following two ways:
EITHER
You have set android:noHistory = "true" for MainActivity inside Androi...
How do you Force Garbage Collection from the Shell?
... java.lang:type=Memory
#bean is set to java.lang:type=Memory
$>run gc
#calling operation gc of mbean java.lang:type=Memory
#operation returns:
null
$>quit
#bye
Look at the docs on the jmxterm web site for information about embedding this in bash/perl/ruby/other scripts. I've used popen2 in ...
How to implement a queue using two stacks?
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Keep 2 stacks, let's call them inbox and outbox.
Enqueue:
Push the new element onto inbox
Dequeue:
If outbox is empty, refill it by popping each element from inbox and pushing it onto outbox
Pop and return the top element from outbox
Usin...
How do I ignore ampersands in a SQL script running from SQL Plus?
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In log4j, does checking isDebugEnabled before logging improve performance?
...using Log4J in my application for logging. Previously I was using debug call like:
16 Answers
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How to remove all debug logging calls before building the release version of an Android app?
According to Google, I must " deactivate any calls to Log methods in the source code " before publishing my Android app to Google Play. Extract from section 3 of the publication checklist :
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How to search file text for a pattern and replace it with a given value
...ull. This code is not fit for anything beyond a quick one-off script where all the data is backed up. For that reason, do NOT copy this code into your programs.
Here's a quick short way to do it.
file_names = ['foo.txt', 'bar.txt']
file_names.each do |file_name|
text = File.read(file_name)
ne...