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Unique Constraint in Entity Framework Code First
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Starting with EF 6.1 it is now possible:
[Index(IsUnique = true)]
public string EmailAddress { get; set; }
This will get you a unique index instead of unique constraint, strictly speaking. For most practical purposes they are the same.
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IPC performance: Named Pipe vs Socket
Everyone seems to say named pipes are faster than sockets IPC. How much faster are they? I would prefer to use sockets because they can do two-way communication and are very flexible but will choose speed over flexibility if it is by considerable amount.
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How do I convert an integer to string as part of a PostgreSQL query?
How do I convert an integer to string as part of a PostgreSQL query?
3 Answers
3
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A std::map that keep track of the order of insertion?
I currently have a std::map<std::string,int> that stores an integer value to an unique string identifier, and I do look up with the string. It does mostly what I want, except for that it does not keep track of the insertion order. So when I iterate the the map to print out the values, they a...
When should I use C++ private inheritance?
...educe space consumption where it really matters, e.g. in policy controlled string classes or in compressed pairs. actually, boost::compressed_pair used protected inheritance.
– Johannes Schaub - litb
Mar 17 '09 at 22:12
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Convert Unicode to ASCII without errors in Python
...odules (in Python 3):
import gzip
import io
Note: In Python 2 you'd use StringIO instead of io
Then you can parse the content out like this:
response = urlopen("https://example.com/gzipped-ressource")
buffer = io.BytesIO(response.read()) # Use StringIO.StringIO(response.read()) in Python 2
gzip...
Different ways of adding to Dictionary
...e value of the key if it already exists in the dictionary.
IDictionary<string, string> strings = new Dictionary<string, string>();
strings["foo"] = "bar"; //strings["foo"] == "bar"
strings["foo"] = string.Empty; //strings["foo"] == string.empty
strings.Add("foo", "bar"); ...
What is a word boundary in regex?
...osition between \w and \W (non-word char), or at the beginning or end of a string if it begins or ends (respectively) with a word character ([0-9A-Za-z_]).
So, in the string "-12", it would match before the 1 or after the 2. The dash is not a word character.
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Convert NSData to String?
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Objective-C
You can use (see NSString Class Reference)
- (id)initWithData:(NSData *)data encoding:(NSStringEncoding)encoding
Example:
NSString *myString = [[NSString alloc] initWithData:myData encoding:NSUTF8StringEncoding];
Remark: Please notice the NSD...
How can I start PostgreSQL server on Mac OS X?
...ver.log?
Make sure tcp localhost connections are enabled in pg_hba.conf:
# IPv4 local connections:
host all all 127.0.0.1/32 trust
Check the listen_addresses and port in postgresql.conf:
egrep 'listen|port' /usr/local/var/postgres/postgresql.conf
#listen_addresses = 'localhost' #...