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Convert seconds to Hour:Minute:Second
...ed to that of the TIME data type, which is from -838:59:59 to 838:59:59 :
SELECT SEC_TO_TIME(8525);
# 02:22:05
See: SEC_TO_TIME
Run the Demo
PostgreSQL example:
SELECT TO_CHAR('8525 second'::interval, 'HH24:MI:SS');
# 02:22:05
Run the Demo
...
Finding index of character in Swift String
...ring doesn't implement RandomAccessIndexType. Probably because they enable characters with different byte lengths. That's why we have to use string.characters.count (count or countElements in Swift 1.x) to get the number of characters. That also applies to positions. The _position is probably an ind...
In C# what is the difference between ToUpper() and ToUpperInvariant()?
...d to hear that there are various other capitalization issues around elided characters etc. This is just one example I know off the top of my head... partly because it bit me years ago in Java, where I was upper-casing a string and comparing it with "MAIL". That didn't work so well in Turkey...
...
Unresolved external symbol on static class members
...ou must add the definitions to match your declarations of X and Y
unsigned char test::X;
unsigned char test::Y;
somewhere. You might want to also initialize a static member
unsigned char test::X = 4;
and again, you do that in the definition (usually in a CXX file) not in the declaration (which is...
MD5 algorithm in Objective-C
...cess
@implementation NSString (MyAdditions)
- (NSString *)md5
{
const char *cStr = [self UTF8String];
unsigned char result[CC_MD5_DIGEST_LENGTH];
CC_MD5( cStr, (int)strlen(cStr), result ); // This is the md5 call
return [NSString stringWithFormat:
@"%02x%02x%02x%02x%02x%02x%...
Storing sex (gender) in database
...,147,483,648 to 2,147,483,647
BIT 1 (2 if 9+ columns) 2 (0 and 1)
CHAR(1) 1 26 if case insensitive, 52 otherwise
The BIT data type can be ruled out because it only supports two possible genders which is inadequate. While INT supports more than two options, it takes...
Installing Google Protocol Buffers on mac
...: implicit instantiation of undefined template 'std::__1::basic_istream<char, std::__1::char_traits<char> >'
return ParseFromZeroCopyStream(&zero_copy_input) && input->eof();
^
/Applications/Xcode.app/Co...
Calling constructors in c++ without new
...new object on the stack by calling a constructor of the format Thing(const char*).
The second one is a bit more complex. It essentially does the following
Create an object of type Thing using the constructor Thing(const char*)
Create an object of type Thing using the constructor Thing(const Th...
static constructors in C++? I need to initialize private static objects
... a class with a private static data member (a vector that contains all the characters a-z). In java or C#, I can just make a "static constructor" that will run before I make any instances of the class, and sets up the static data members of the class. It only gets run once (as the variables are read...
Getting file names without extensions
... Directory.GetFiles(@"c:\", "*.txt")
.Select(filename =>
Path.GetFileNameWithoutExtension(filename)));
I dislike the DirectoryInfo, FileInfo for this scenario.
DirectoryInfo and FileInfo collect more data about the folder and the...