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PostgreSQL error 'Could not connect to server: No such file or directory'
...u are on OS X
Here is the fix:
Stop the database
cd /var
sudo rm -r pgsql_socket
sudo ln -s /tmp pgsql_socket
chown _postgres:_postgres pgsql_socket
Restart PostgreSQL (not your computer)
More information is available at "postgresql 9.0.3. on Lion Dev Preview 1".
...
Error: Could not create the Java Virtual Machine Mac OSX Mavericks
I just installed the latest Java SDK 7-67 from Oracle on the Mac 10.9.4. I then ran the command java -v in Terminal and I get this message:
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Is there a Mutex in Java?
...ock;
import java.util.concurrent.locks.ReentrantLock;
private final Lock _mutex = new ReentrantLock(true);
_mutex.lock();
// your protected code here
_mutex.unlock();
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Python add item to the tuple
... @SIslam Without the comma, it will just be interpreted as brackets usually used to get around the order of precedence: (a+b)*c
– Joseph Young
Feb 25 '16 at 5:54
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Why should hash functions use a prime number modulus?
...
Usually a simple hash function works by taking the "component parts" of the input (characters in the case of a string), and multiplying them by the powers of some constant, and adding them together in some integer type. So for e...
Array.push() if does not exist?
... it doesn't then just push the item into the array:
var newItem = "NEW_ITEM_TO_ARRAY";
var array = ["OLD_ITEM_1", "OLD_ITEM_2"];
array.indexOf(newItem) === -1 ? array.push(newItem) : console.log("This item already exists");
console.log(array)
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Read only the first line of a file?
...od (Python 2 docs, Python 3 docs):
with open('myfile.txt') as f:
first_line = f.readline()
Some notes:
As noted in the docs, unless it is the only line in the file, the string returned from f.readline() will contain a trailing newline. You may wish to use f.readline().strip() instead to rem...
Multiple DB Contexts in the Same DB and Application in EF 6 and Code First Migrations
...lied to the target database.
Applying explicit migrations: [201402032113124_InitialDatabaseCreation].
Applying explicit migration: 201402032113124_InitialDatabaseCreation.
Running Seed method.
PM> Update-Database -ConfigurationTypeName WebApplication3.Migrations.AnotherDbContext.Configuration
Sp...
What is the difference between pull and clone in git?
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They're basically the same, except clone will setup additional remote tracking branches, not just master. Check out the man page:
Clones a repository into a newly created directory, creates remote-tracking branches for each branch in ...
How can I use Guzzle to send a POST request in JSON?
... edited Aug 18 at 7:06
Valor_
2,49255 gold badges3939 silver badges8787 bronze badges
answered Mar 7 '14 at 8:56
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