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How to limit the amount of concurrent async I/O operations?
... client = new HttpClient();
var html = await client.GetStringAsync(url);
}
finally
{
throttler.Release();
}
}));
}
// won't get here until all urls have been put into tasks
...
How do I specify unique constraint for multiple columns in MySQL?
... That way combination of three would be unique? Or all individual three columns would be unique?
– Gary Lindahl
Sep 15 '11 at 0:03
100
...
Is std::vector copying the objects with a push_back?
...object class.
class object
{
private:
int m_val1;
std::string m_val2;
public:
// Constructor for object class.
object(int val1, std::string &&val2) :
m_val1(val1),
m_val2(std::move(val2))
{
}
};
std::vector<object> myList;
// ...
Oracle: how to UPSERT (update or insert into a table?)
... and the update where another process could successfully fire a delete. I did however use this pattern on a table that never has deletes fired against it.
– chotchki
Sep 29 '11 at 22:50
...
How do I make and use a Queue in Objective-C?
...tableArray+QueueAdditions.h
@interface NSMutableArray (QueueAdditions)
- (id) dequeue;
- (void) enqueue:(id)obj;
@end
NSMutableArray+QueueAdditions.m
@implementation NSMutableArray (QueueAdditions)
// Queues are first-in-first-out, so we remove objects from the head
- (id) dequeue {
// if ([...
How to have an automatic timestamp in SQLite?
...
Just declare a default value for a field:
CREATE TABLE MyTable(
ID INTEGER PRIMARY KEY,
Name TEXT,
Other STUFF,
Timestamp DATETIME DEFAULT CURRENT_TIMESTAMP
);
However, if your INSERT command explicitly sets this field to NULL, it will be set to NULL.
...
Can I add extension methods to an existing static class?
...tionManagerWrapper
{
public static ConfigurationSection GetSection( string name )
{
return ConfigurationManager.GetSection( name );
}
.....
public static ConfigurationSection GetWidgetSection()
{
return GetSection( "widgets" );
}
}
...
How to echo or print an array in PHP?
...t;pre>";
var_dump($arr);
echo "</pre>";
array(3) {
[0]=>
string(1) "a"
[1]=>
string(1) "b"
[2]=>
string(1) "c"
}
var_export()
Displays structured information about the given variable that returned representation is valid PHP code.
echo "<pre>";
var_export(...
How to change max_allowed_packet size
...on. He made a mistake of putting it at the bottom of the file first so it did not work.
6) Control + O (save) then ENTER (confirm) then Control + X (exit file)
7) service mysqld restart
8) You can check the change in the variables section on phpmyadmin
...
How to beautify JSON in Python?
...t with aiohttp on python3.7, didn't need to use the sys module and unicode(String, encoding). Basically it becomes == highlight(formatted_json, lexers.JsonLexer(), formatters.TerminalFormatter())
– DanglingPointer
Sep 26 '18 at 6:49
...