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What does void* mean and how to use it?
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Before void pointers were available "char *" was used instead. But void is better as it cannot actually be used to alter anything directly.
– user50619
Jun 4 '19 at 13:08
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How to pull a random record using Django's ORM?
...on't know about other databases).
order_by('?')[:N] will be translated to SELECT ... FROM ... WHERE ... ORDER BY RAND() LIMIT N query.
It means that for every row in table the RAND() function will be executed, then the whole table will be sorted according to value of this function and then first N...
How to add a line break in C# .NET documentation
...p;#160;</para>, <para>&nbsp;</para> or the invisible character...
– Dinei
Oct 23 '14 at 14:30
Th...
How to Create Multiple Where Clause Query Using Laravel Eloquent?
...;orWhere($orThose)
->get();
The above will result in such query:
SELECT * FROM users
WHERE (field = value AND another_field = another_value AND ...)
OR (yet_another_field = yet_another_value AND ...)
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Java executors: how to be notified, without blocking, when a task completes?
... {
sleep(7000, TimeUnit.MILLISECONDS); /* Pretend to be busy... */
char[] str = new char[5];
ThreadLocalRandom current = ThreadLocalRandom.current();
for (int idx = 0; idx < str.length; ++idx)
str[idx] = (char) ('A' + current.nextInt(26));
String msg = new String(str);
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What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
...Core Foundation objects and memory allocated using malloc() for types like char*. ARC does not manage these types, only Objective-C objects, so you'll still need to deal with them yourself. Core Foundation types can be particularly tricky, because sometimes they need to be bridged across to matchi...
Get list of all tables in Oracle?
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SELECT owner, table_name
FROM dba_tables
This is assuming that you have access to the DBA_TABLES data dictionary view. If you do not have those privileges but need them, you can request that the DBA explicitly grants you...
Type erasure techniques
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I would also consider (similar to void*) the use of "raw storage": char buffer[N].
In C++0x you have std::aligned_storage<Size,Align>::type for this.
You can store anything you want in there, as long as it's small enough and you deal with the alignment properly.
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Why does “_” (underscore) match “-” (hyphen)?
...u want to use the underscore in like as a literal, you have to escape it:
select * from a where name like '%taz\_manual%.pdf%';
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Left-pad printf with spaces
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If you want the word "Hello" to print in a column that's 40 characters wide, with spaces padding the left, use the following.
char *ptr = "Hello";
printf("%40s\n", ptr);
That will give you 35 spaces, then the word "Hello". This is how you format stuff when you know how wide you wa...