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How to create an object for a Django model with a many to many field?
...e_object.users.add(1,2)
Update: After reading the saverio's answer, I decided to investigate the issue a bit more in depth. Here are my findings.
This was my original suggestion. It works, but isn't optimal. (Note: I'm using Bars and a Foo instead of Users and a Sample, but you get the idea).
ba...
How to construct a set out of list items in python?
...
If you have a list of hashable objects (filenames would probably be strings, so they should count):
lst = ['foo.py', 'bar.py', 'baz.py', 'qux.py', Ellipsis]
you can construct the set directly:
s = set(lst)
In fact, set will work this way with any iterable object! (Isn't duck typing gre...
Can I obtain method parameter name using Java reflection?
...mments) there are a few options:
use arg0, arg1, arg2 etc.
use intParam, stringParam, objectTypeParam, etc.
use a combination of the above - the former for non-primitive types, and the latter for primitive types.
don't show argument names at all - just the types.
...
How to check whether a file or directory exists?
...exists returns whether the given file or directory exists
func exists(path string) (bool, error) {
_, err := os.Stat(path)
if err == nil { return true, nil }
if os.IsNotExist(err) { return false, nil }
return false, err
}
Edited to add error handling.
...
MySQL ON DUPLICATE KEY - last insert id?
...e.html
At the bottom of the page they explain how you can make LAST_INSERT_ID meaningful for updates by passing an expression to that MySQL function.
From the MySQL documentation example:
If a table contains an AUTO_INCREMENT column and INSERT ... UPDATE inserts a row, the LAST_INSERT_ID() func...
What's the difference between URI.escape and CGI.escape?
...ll it depends on what you need to do.
URI.escape was supposed to encode a string (URL) into, so called, "Percent-encoding".
CGI::escape is coming from the CGI spec, which describes how data should be encoded/decode between web server and application.
Now, let's say that you need to escape a URI ...
How to get cumulative sum
...
select t1.id, t1.SomeNumt, SUM(t2.SomeNumt) as sum
from @t t1
inner join @t t2 on t1.id >= t2.id
group by t1.id, t1.SomeNumt
order by t1.id
SQL Fiddle example
Output
| ID | SOMENUMT | SUM |
-----------------------
| 1 | 1...
How to establish a connection pool in JDBC?
... Object, reducing the Garbage collection load.
« Pooling [ Object pool, String Constant Pool, Thread Pool, Connection pool]
String Constant pool
String literal pool maintains only one copy of each distinct string value. which must be immutable.
When the intern method is invoked, it check objec...
Suppress warning CS1998: This async method lacks 'await'
...ter]
[MemoryDiagnoser]
public class BenchmarkAsyncNotAwaitInterface
{
string context = "text context";
[Benchmark]
public int CompletedAwait()
{
var t = new CompletedAwaitTest();
var a = t.DoAsync(context);
a.Wait();
return t.Length;
}
[Benchmark]
public int Completed()
{
v...
Can't execute jar- file: “no main manifest attribute”
...ere com.mypackage.MyClass is the class holding the public static void main(String[] args) entry point.
Note that there are several ways to get this done either with the CLI, Maven, Ant or Gradle:
For CLI, the following command will do: (tks @dvvrt)
jar cmvf META-INF/MANIFEST.MF <new-jar-filename&...