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Unique constraint on multiple columns
...ied from technet's documentation, is in the form of:
CONSTRAINT constraint_name UNIQUE [ CLUSTERED | NONCLUSTERED ]
(
column [ ASC | DESC ] [ ,...n ]
)
Therefore, the resuting table definition would be:
CREATE TABLE [dbo].[user](
[userID] [int] IDENTITY(1,1) NOT NULL,
[fcode] [int] ...
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".
...
Symbolicating iPhone App Crash Reports
...
Also, if used without an address, it allow you to analyse multiple locations by submitting them one by one.
– Paul Ardeleanu
Mar 12 '12 at 10:03
...
Is it a good practice to use try-except-else in Python?
...o, the use of exceptions in Python does not slow the surrounding code and calling code as it does in some compiled languages (i.e. CPython already implements code for exception checking at every step, regardless of whether you actually use exceptions or not).
In other words, your understanding that...
How to import an existing X.509 certificate and private key in Java keystore to use in SSL?
...
For what it's worth, for all the noise on this subject, the best link is @Matej's 'workaround' link to this 2008 post: cunning.sharp.fm/2008/06/importing_private_keys_into_a.html
– cloudsurfin
Feb 11 '16 at 0:44...
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...
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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Null vs. False vs. 0 in PHP
...ers can spot/utilize the difference between Null and False and 0 and all the other good "nothing" entities.
What is the difference, specifically in PHP? Does it have something to do with === ?
...
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...
how to debug the js in jsfiddle
...ever using chrome dev tools. Press ctrl+shift+F and you can search through all the files in the source.
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