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SQL - many-to-many table primary key
... index, on (col1, col2) also handles the 'both' case). The downside is the extra storage needed for the extra column. This is usually not significant, so the advice is far from awful. Nevertheless, if col1 and col2 are big or of very different sizes, you can save yourself some space without hurting ...
Match whole string
...ct match? That is, there should be no extra characters at other end of the string.
3 Answers
...
Difference between single and double square brackets in Bash
...nsion.
expr a \< b > /dev/null: POSIX equivalent², see: How to test strings for lexicographic less than or equal in Bash?
&& and ||
[[ a = a && b = b ]]: true, logical and
[ a = a && b = b ]: syntax error, && parsed as an AND command separator cmd1 &&...
Create and append dynamically
...amic this is is, but sometimes this might save your debugging life:
var daString="<div id=\'block\' class=\'block\'><div class=\'block-2\'></div></div>";
var daParent=document.getElementById("the ID of whatever your parent is goes in here");
daParent.innerHTML=daString;
"R...
Fluid width with equally spaced DIVs
...>
<span class="stretch"></span>
</div>
The extra span (.stretch) can be replaced with :after.
This still works in all the same browsers as the above solution. :after doesn't work in IE6/7, but they're using distribute-all-lines anyway, so it doesn't matter.
See: htt...
What is the use of interface constants?
....
Use of Enum Constants is actually Horrible Practice.
It requires writing extra code to map parameter to value. The fact that the founders of Java did not provide for parameter-value mapping without your writing that mapping code demonstrates Enum Constants are just as unintended use of Java langua...
How to get an object's properties in JavaScript / jQuery?
...quired. To know the base class name, you may invoke the Object.prototype.toString method on an object, like this:
alert(Object.prototype.toString.call([]));
The above will output [object Array].
There are several other class names, like [object Object], [object Function], [object Date], [object ...
Is using a lot of static methods a bad thing?
...llowing:
public static class ResourceLoader
{
public static void Init(string _rootPath) { ... etc. }
public static void GetResource(string _resourceName) { ... etc. }
public static void Quit() { ... etc. }
}
public static class TextureManager
{
private static Dictionary<string,...
How can I play sound in Java?
...y works with .wav format.
public static synchronized void playSound(final String url) {
new Thread(new Runnable() {
// The wrapper thread is unnecessary, unless it blocks on the
// Clip finishing; see comments.
public void run() {
try {
Clip clip = AudioSystem.getClip();
...
How to deal with a slow SecureRandom generator?
...RNG, do something like this:
SecureRandom.getInstance("SHA1PRNG");
What strings are supported depends on the SecureRandom SPI provider, but you can enumerate them using Security.getProviders() and Provider.getService().
Sun is fond of SHA1PRNG, so it's widely available. It isn't especially fast ...