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MySQL Cannot drop index needed in a foreign key constraint
I need to ALTER my existing database to add a column. Consequently I also want to update the UNIQUE field to encompass that new column. I'm trying to remove the current index but keep getting the error MySQL Cannot drop index needed in a foreign key constraint
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How do I pass a class as a parameter in Java?
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public void foo(Class c){
try {
Object ob = c.newInstance();
} catch (InstantiationException ex) {
Logger.getLogger(App.class.getName()).log(Level.SEVERE, null, ex);
} catch (Ille...
Pick a random value from an enum?
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The only thing I would suggest is caching the result of values() because each call copies an array. Also, don't create a Random every time. Keep one. Other than that what you're doing is fine. So:
public enum Letter {
A,
B,
C,
//...
private static final List<Letter> VALUE...
How do I preserve line breaks when using jsoup to convert html to plain text?
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The real solution that preserves linebreaks should be like this:
public static String br2nl(String html) {
if(html==null)
return html;
Document document = Jsoup.parse(html);
document.outputSettings(new Document.OutputSettings().prettyPrint(f...
How can I test an AngularJS service from the console?
...DR: In one line the command you are looking for:
angular.element(document.body).injector().get('serviceName')
Deep dive
AngularJS uses Dependency Injection (DI) to inject services/factories into your components,directives and other services. So what you need to do to get a service is to get th...
Change select box option background color
I have a select box and I'm trying to change the background color of the options when the select box has been clicked and shows all the options.
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Git-Based Source Control in the Enterprise: Suggested Tools and Practices?
I use git for personal projects and think it's great. It's fast, flexible, powerful, and works great for remote development.
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Calling dynamic function with dynamic number of parameters [duplicate]
I’m looking for a trick about this. I know how to call a dynamic, arbitrary function in JavaScript, passing specific parameters, something like this:
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AWK: Access captured group from line pattern
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That was a stroll down memory lane...
I replaced awk by perl a long time ago.
Apparently the AWK regular expression engine does not capture its groups.
you might consider using something like :
perl -n -e'/test(\d+)/ && print $1'
the -n flag causes perl to loop ove...
“loop:” in Java code. What is this, and why does it compile?
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It is not a keyword it is a label.
Usage:
label1:
for (; ; ) {
label2:
for (; ; ) {
if (condition1) {
// break outer loop
break label1;
}
if (condition2) {
...