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Adding 'serial' to existing column in Postgres
I have a small table (~30 rows) in my Postgres 9.0 database with an integer ID field (the primary key) which currently contains unique sequential integers starting at 1, but which was not created using the 'serial' keyword.
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What is a None value?
...s the None value, but unfortunately this book isn't very clear at some points. I thought that I would find the answer to my question, if I share it there.
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Difference between size_t and std::size_t
...re the same as C header (see the quotation below). Its defined as unsigned integer type of the result of the sizeof operator.
C Standard says in §17.7/2,
size_t which is the unsigned integer type of the result of the sizeof operator
And C++ Standard says (about cstddef header) in §18.1/3,
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Handler vs AsyncTask vs Thread [closed]
... Synchronization with the main thread if you post back results to the user interface
No default for canceling the thread
No default thread pooling
No default for handling configuration changes in Android
And regarding the AsyncTask, as the Android Developer's Reference puts it:
AsyncT...
Does MySQL ignore null values on unique constraints?
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Yes, MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
INSERT table1 VALUES (NULL);
SELECT * FROM table1;
Result:...
Why does the use of 'new' cause memory leaks?
...e duration. It won't get cleaned up automatically.
You need to pass a pointer to it to delete in order to clean it up:
However, your second example is worse: you're dereferencing the pointer, and making a copy of the object. This way you lose the pointer to the object created with new, so you ...
How can you integrate a custom file browser/uploader with CKEditor?
The official documentation is less than clear - what's the correct way to integrate a custom file browser/uploader with CKEditor? (v3 - not FCKEditor)
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How to properly add cross-site request forgery (CSRF) token using PHP
...pen source projects is an initiative to backport random_bytes() and random_int() into PHP 5 projects. It's MIT licensed and available on Github and Composer as paragonie/random_compat.
PHP 5.3+ (or with ext-mcrypt)
session_start();
if (empty($_SESSION['token'])) {
if (function_exists('mcrypt_c...
Does the use of the “Async” suffix in a method name depend on whether the 'async' modifier is used?
...for example, or async void.
Of course, you have to consider what is the point of the convention?
You could say that the Async suffix convention is to communicate to the API user that the method is awaitable. For a method to be awaitable, it must return Task for a void, or Task<T> for a value...
What is the difference between char s[] and char *s?
...place "Hello world" in the read-only parts of the memory, and making s a pointer to that makes any writing operation on this memory illegal.
While doing:
char s[] = "Hello world";
puts the literal string in read-only memory and copies the string to newly allocated memory on the stack. Thus maki...