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How do MySQL indexes work?
...lision number is high cause you'll only perform the second comparison (the string one) against the repeated hashes.
Unfortunately, using this technique, you still need to hit the table to compare the url field.
Wrap up
Some facts that you may consider every time you want to talk about optimizatio...
Remove elements from collection while iterating
...
Old Timer Favorite (it still works):
List<String> list;
for(int i = list.size() - 1; i >= 0; --i)
{
if(list.get(i).contains("bad"))
{
list.remove(i);
}
}
Benefits:
It only iterates over the list once
No extra objects ...
Looking for a clear definition of what a “tokenizer”, “parser” and...
...hes extra context to the tokens -- this token is a number, that token is a string literal, this other token is an equality operator.
A parser takes the stream of tokens from the lexer and turns it into an abstract syntax tree representing the (usually) program represented by the original text.
Las...
Set cookie and get cookie with JavaScript [duplicate]
...Time() + (days*24*60*60*1000));
expires = "; expires=" + date.toUTCString();
}
document.cookie = name + "=" + (value || "") + expires + "; path=/";
}
function getCookie(name) {
var nameEQ = name + "=";
var ca = document.cookie.split(';');
for(var i=0;i < ca.length;i++...
Use logging print the output of pprint
...
Use pprint.pformat to get a string, and then send it to your logging framework.
from pprint import pformat
ds = [{'hello': 'there'}]
logging.debug(pformat(ds))
share
...
What is a Java ClassLoader?
...ollowing simple class:
public class HelloApp {
public static void main(String argv[]) {
System.out.println("Aloha! Hello and Bye");
}
}
If you run this class specifying the -verbose:class command-line option, so that it prints what classes are being loaded, you will get an output that...
NodeJS - Error installing with NPM
...t least) 2 ways to resolve this.
Installing the Cygwin package cygutils-extra and use winln.
Use native Windows CMD in Admin mode.
For (1) you can create a proper symlink from within Cygwin shell by doing these steps:
# To make the Cygwin environment treat Windows links properly:
# Alternat...
Creating C macro with ## and __LINE__ (token concatenation with positioning macro)
...the token-pasting operator ## are applied to it. So, you have to use some extra layers of indirection, you can use the token-pasting operator with a recursively expanded argument:
#define TOKENPASTE(x, y) x ## y
#define TOKENPASTE2(x, y) TOKENPASTE(x, y)
#define UNIQUE static void TOKENPASTE2(Uniq...
Get MIME type from filename extension
...ing.GetMimeMapping method, that is part of the BCL in .NET Framework 4.5:
string mimeType = MimeMapping.GetMimeMapping(fileName);
If you need to add custom mappings you probably can use reflection to add mappings to the BCL MimeMapping class, it uses a custom dictionary that exposes this method, ...
Cycles in family tree software
...ernally should be going to A on presentation of data.
This will make some extra work for the user, but I guess IT would be relatively easy to implement and maintain.
Building from that, you could work on code synching A and B to avoid inconsistencies.
This solution is surely not perfect, but is a...