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How do I tell if a regular file does not exist in Bash?
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The test command ([ here) has a "not" logical operator which is the exclamation point (similar to many other languages). Try this:
if [ ! -f /tmp/foo.txt ]; then
echo "File not found!"
fi
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Using a constant NSString as the key for NSUserDefaults
...mber reading somewhere that setting the keys as constants is a good idea - and I agree. The following code is what I currently have:
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What's the scope of the “using” declaration in C++?
I'm using the 'using' declaration in C++ to add std::string and std::vector to the local namespace (to save typing unnecessary 'std::'s).
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PostgreSQL - fetch the row which has the Max value for a column
...that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
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How to set variables in HIVE scripts
...where day >= ${hiveconf:CURRENT_DATE}
similarly, you could pass on command line:
% hive -hiveconf CURRENT_DATE='2012-09-16' -f test.hql
Note that there are env and system variables as well, so you can reference ${env:USER} for example.
To see all the available variables, from the command line, ...
How to delete all datastore in Google App Engine?
...re --> dataviewer, select all the rows for the table you want to delete and hit the delete button (you'll have to do this for all your tables).
You can do the same programmatically through the remote_api (but I never used it).
If you're talking about the development datastore, you'll just have ...
Android global variable
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You can extend the base android.app.Application class and add member variables like so:
public class MyApplication extends Application {
private String someVariable;
public String getSomeVariable() {
return someVariable;
}
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How do I run NUnit in debug mode from Visual Studio?
...a test framework for a bit of C# I've been working on. I have NUnit set up and a new project within my workspace to test the component. All works well if I load up my unit tests from Nunit (v2.4), but I've got to the point where it would be really useful to run in debug mode and set some break point...
What are some good Python ORM solutions? [closed]
I'm evaluating and looking at using CherryPy for a project that's basically a JavaScript front-end from the client-side (browser) that talks to a Python web service on the back-end. So, I really need something fast and lightweight on the back-end that I can implement using Python that then speaks to...
How to add/update an attribute to an HTML element using JavaScript?
... answered Apr 2 '09 at 15:52
andiandi
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