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SQL query return data from multiple tables
...I-89 syntax (and if you are used to 89, may seem much less intuitive - but all I can say is to try it) as it is much easier to understand when the queries start getting more complex. Why use it? Is there a performance gain? The short answer is no, but it is easier to read once you get used to it. It...
What is a 'Closure'?
... scope
When you declare a local variable, that variable has a scope. Generally, local variables exist only within the block or function in which you declare them.
function() {
var a = 1;
console.log(a); // works
}
console.log(a); // fails
If I try to access a local variable, most languag...
Does svn have a `revert-all` command?
If I want to throw away all of my changes, and return to the code that is on the repository, I do the following:
4 Answers
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in_array multiple values
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if(count(array_intersect($haystack, $target)) == count($target)){
// all of $target is in $haystack
}
Note that you only need to verify the size of the resulting intersection is the same size as the array of target values to say that $haystack is a superset of $target.
To verify that at lea...
ASP.NET MVC ambiguous action methods
I have two action methods that are conflicting. Basically, I want to be able to get to the same view using two different routes, either by an item's ID or by the item's name and its parent's (items can have the same name across different parents). A search term can be used to filter the list.
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Creating a copy of a database in PostgreSQL [closed]
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Postgres allows the use of any existing database on the server as a template when creating a new database. I'm not sure whether pgAdmin gives you the option on the create database dialog but you should be able to execute the following...
How to deny access to a file in .htaccess
...nes from the parent).
So you can have:
<Files "log.txt">
Order Allow,Deny
Deny from all
</Files>
For Apache 2.4+, you'd use:
<Files "log.txt">
Require all denied
</Files>
In an htaccess file in your inscription directory. Or you can use mod_rewrite to sort of...
Git add and commit in one command
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is an easy way to tell git to delete files you have deleted, but I generally don't recommend such catch-all workflows. Git commits should in best practice be fairly atomic and only affect a few files.
git add .
git commit -m "message"
is an easy way to add all files new or modified. Also, the ...
Clear back stack using fragments
...tBackStackEntryCount(); ++i) {
fm.popBackStack();
}
But could equally have used something like:
((AppCompatActivity)getContext()).getSupportFragmentManager().popBackStack(String name, FragmentManager.POP_BACK_STACK_INCLUSIVE)
Which will pop all states up to the named one. You can then j...
How do you find the sum of all the numbers in an array in Java?
I'm having a problem finding the sum of all of the integers in an array in Java. I cannot find any useful method in the Math class for this.
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