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Which data type for latitude and longitude?
I am newbie to PostgreSQL and PostGIS. I want to store latitude and longitude values in PostgreSQL 9.1.1 database table. I will calculate distance between two points, find nearer points by using this location values.
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How to Remove Array Element and Then Re-Index Array?
...t to modify like below. I want to remove element (elements) of it by index and then re-index array. Is it possible?
9 Answe...
How to obtain Signing certificate fingerprint (SHA1) for OAuth 2.0 on Android?
I'm trying to register my android app following the steps in https://developers.google.com/console/help/#installed_applications which leads me to follow
http://developer.android.com/tools/publishing/app-signing.html .
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How to secure MongoDB with username and password
... for the user name & password. I tried the tutorial from the MongoDB site and did following:
15 Answers
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What is the difference between mutex and critical section?
... between the two of them. On my system for 1,000,000 uncontended acquires and releases, a mutex takes over one second. A critical section takes ~50 ms for 1,000,000 acquires.
Here's the test code, I ran this and got similar results if mutex is first or second, so we aren't seeing any other effect...
How can I see what has changed in a file before committing to git?
...ere are three useful ways to use git diff:
Show differences between index and working tree; that is, changes you haven't staged to commit:
git diff [filename]
Show differences between current commit and index; that is, what you're about to commit (--staged does exactly the same thing, use what y...
What's the simplest way to print a Java array?
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Since Java 5 you can import java.util.Arrays; and then use Arrays.toString(arr) or Arrays.deepToString(arr) for arrays within arrays. Note that the Object[] version calls .toString() on each object in the array. The output is even decorated in the exact way you're asking...
Tricks to manage the available memory in an R session
...ive R session? I use the functions below [based on postings by Petr Pikal and David Hinds to the r-help list in 2004] to list (and/or sort) the largest objects and to occassionally rm() some of them. But by far the most effective solution was ... to run under 64-bit Linux with ample memory.
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What is the difference between old style and new style classes in Python?
What is the difference between old style and new style classes in Python? When should I use one or the other?
8 Answers
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How to find out the MySQL root password
...log --skip-networking
Then run mysql in a new terminal:
mysql -u root
And run the following queries to change the password:
UPDATE mysql.user SET authentication_string=PASSWORD('password') WHERE User='root';
FLUSH PRIVILEGES;
In MySQL 5.7, the password field in mysql.user table field was rem...