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Rails: select unique values from a column
...rks only on "top level" queries, like above. Doesn't work on collection prom>x m>ies ("has_many" relations, for em>x m>ample).
Address.distinct.pluck(:city) # => ['Moscow']
user.addresses.distinct.pluck(:city) # => ['Moscow', 'Moscow', 'Moscow']
In this case, deduplicate after the query
user.address...
Is inline assembly language slower than native C++ code?
...fluence performance (as you saw in this case).
You can always produce an em>x m>ample where handmade assembly code is better than compiled code but usually it's a fictional em>x m>ample or a single routine not a true program of 500.000+ lines of C++ code). I think compilers will produce better assembly code ...
Convert pem key to ssh-rsa format
...eygen):
-m key_format Specify a key format for the -i (import) or -e (em>x m>port) conversion options. The supported key formats are: “RFC4716” (RFC 4716/SSH2 public or private key), “PKCS8” (PEM PKCS8 public key) or “PEM” (PEM public key). The default conversion format is “RFC4716”...
Difference Between Invoke and DynamicInvoke
...e between Invoke and DynamicInvoke in delegates? Please give me some code em>x m>ample which em>x m>plain difference between that two methods.
...
Difference between char* and const char*?
...to (https://msdn.microsoft.com/en-us/library/vstudio/whkd4k6a(v=vs.100).aspm>x m>, see "Em>x m>amples"). In this case, the const specifier applies to char, not the asterisk.
According to the MSDN page and http://en.cppreference.com/w/cpp/language/declarations, the const before the * is part of the decl-speci...
in entity framework code first, how to use KeyAttribute on multiple columns
...olumn, and specifically, how can I control order of the columns in the indem>x m>? Is it a result of the order of properties in the class?
...
How to read keyboard-input?
... numeric value
just convert it:
try:
mode=int(raw_input('Input:'))
em>x m>cept ValueError:
print "Not a number"
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Load RSA public key from file
...vateKeyReader {
public static PrivateKey get(String filename)
throws Em>x m>ception {
byte[] keyBytes = Files.readAllBytes(Paths.get(filename));
PKCS8EncodedKeySpec spec =
new PKCS8EncodedKeySpec(keyBytes);
KeyFactory kf = KeyFactory.getInstance("RSA");
return kf.generatePriv...
The specified type member 'Date' is not supported in LINQ to Entities. Only initializers, entity mem
...tsCustomByUniqueStudentReference(userDevice.UniqueStudentReference)
.Where(m>x m> => EntityFunctions.TruncateTime(m>x m>.DateTimeStart) == currentDate.Date);
UPDATE: As @shankbond mentioned in comments, in Entity Framework 6 EntityFunctions is obsolete, and you should use DbFunctions class, which is ship...
Why does “,,,” == Array(4) in Javascript?
...length of the array to that number. So you can say you have four empty indem>x m>es (same as [,,,]) and the default string representation of arrays is a comma-separated list of its elements:
> ['a','b','c'].toString()
"a,b,c"
How the comparison works is described in section 11.9.3 of the specif...