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MongoDB aggregation framework match OR
...n' }] }
Like so, since the $match operator just takes what you would normally put into the find() function
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Why do we need C Unions?
...le types together:
enum Type { INTS, FLOATS, DOUBLE };
struct S
{
Type s_type;
union
{
int s_ints[2];
float s_floats[2];
double s_double;
};
};
void do_something(struct S *s)
{
switch(s->s_type)
{
case INTS: // do something with s->s_ints
break;
case F...
Why does PHP 5.2+ disallow abstract static class methods?
...2, I saw a load of strict standards warnings from a project that was originally written without strict warnings:
8 Answers
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How to set UICollectionViewDelegateFlowLayout?
...and this will only work if self.collectionView.collectionViewLayout is actually set to your flow layout. (or set with initWithFrame:collectionViewLayout:)
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What do the return values of node.js process.memoryUsage() stand for?
... Scheme first.
A running program is always represented through some space allocated in memory. This space is called Resident Set. V8 uses a scheme similar to the Java Virtual Machine and divides the memory into segments:
Code: the actual code being executed
Stack: contains all value types (prim...
git submodule tracking latest
...6:
submodule add: If --branch is given, record it in .gitmodules
This allows you to easily record a submodule.<name>.branch option in .gitmodules when you add a new submodule. With this patch,
$ git submodule add -b <branch> <repository> [<path>]
$ git config -f .gitm...
Running Python code in Vim
...th python
Explanation:
autocmd: command that Vim will execute automatically on {event} (here: if you open a python file)
[i]map: creates a keyboard shortcut to <F9> in insert/normal mode
<buffer>: If multiple buffers/files are open: just use the active one
<esc>: leaving insert...
What is the difference between HAVING and WHERE in SQL?
...nt(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities in MA with more than 5 address...
How do I restore a missing IIS Express SSL Certificate?
...press, according to such articles as this and this , I am unable to actually load an IIS Express site using HTTPS. In Chrome , I am only getting:
...
How do I get the last inserted ID of a MySQL table in PHP?
...ng PDO, use PDO::lastInsertId.
If you're using Mysqli, use mysqli::$insert_id.
If you're still using Mysql:
Please, don't use mysql_* functions in new code. They are no longer maintained and are officially deprecated. See the red box? Learn about prepared statements instead, and use PDO or MyS...