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Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
...egers, you count starting from 0 and you end at 255. But with places in a string, you count starting from the 1st place, so doesn't it make sense to end at the 256th place, because you started at 1 instead of 0? I'm not agreeing with varchar(256) entirely just yet, because of string_length() resul...
What are the differences between the BLOB and TEXT datatypes in MySQL?
...s.
BLOB is used for storing binary data while Text is used to store large string.
BLOB values are treated as binary strings (byte strings). They have no character set, and sorting and comparison are based on the numeric values of the bytes in column values.
TEXT values are treated as nonbinary st...
How to print color in console using System.out.println?
...you could define constants like these for the colors:
public static final String ANSI_RESET = "\u001B[0m";
public static final String ANSI_BLACK = "\u001B[30m";
public static final String ANSI_RED = "\u001B[31m";
public static final String ANSI_GREEN = "\u001B[32m";
public static final String ANSI_...
Can hash tables really be O(1)?
...ll as the above, if you are using immutable objects as your keys e.g. Java Strings, having calculated the hash once, you can remember it and not have to calculate it again. On the other hand, you can't usually rely on the hash to tell if two keys are equal once you have found the right bucket, so f...
Python str vs unicode types
...unicode instead of str , as both of them seem to be able to hold Unicode strings. Is there any special reason apart from being able to set Unicode codes in unicode strings using the escape char \ ?:
...
Best practice multi language website
...e our translated files instead of calling a translation function for every string in the file:
// This function was written by Thomas Bley, not by me
function translate($file) {
$cache_file = 'cache/'.LANG.'_'.basename($file).'_'.filemtime($file).'.php';
// (re)build translation?
if (!file_ex...
How to make vim paste from (and copy to) system's clipboard?
...efault, but if you install the vim-gtk or vim-gtk3 package you can get the extra features nonetheless.
You also may want to have a look at the 'clipboard' option described in :help cb. In this case you can :set clipboard=unnamed or :set clipboard=unnamedplus to make all yanking/deleting operations a...
Are there any reasons to use private properties in C#?
...
I use them if I need to cache a value and want to lazy load it.
private string _password;
private string Password
{
get
{
if (_password == null)
{
_password = CallExpensiveOperation();
}
return _password;
}
}
...
PHP: How to generate a random, unique, alphanumeric string for use in a secret link?
How would it be possible to generate a random, unique string using numbers and letters for use in a verify link? Like when you create an account on a website, and it sends you an email with a link, and you have to click that link in order to verify your account
...
Regular expression to match any character being repeated more than 10 times
...ckslashes, e.g. Emacs would make you write \(.\)\1\{9,\} here.
If a whole string should consist of 9 or more identical characters, add anchors around the pattern:
my $regex = qr/^(.)\1{9,}$/;
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