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SQL Server Insert if not exists
...ode
BEGIN
INSERT INTO EmailsRecebidos (De, Assunto, Data)
VALUES (@_DE, @_ASSUNTO, @_DATA)
WHERE NOT EXISTS ( SELECT * FROM EmailsRecebidos
WHERE De = @_DE
AND Assunto = @_ASSUNTO
AND Data = @_DATA);
END
replace with
BEGIN
I...
How to avoid explicit 'self' in Python?
...e, and always know whether you are accessing a member or not:
class A(some_function()):
def f(self):
self.member = 42
self.method()
That's the complete code! (some_function returns the type used as a base.)
Another, where the methods of a class are dynamically composed:
class B(objec...
Python constructor and default value [duplicate]
...don't generally do what you want. Instead, try this:
class Node:
def __init__(self, wordList=None, adjacencyList=None):
if wordList is None:
self.wordList = []
else:
self.wordList = wordList
if adjacencyList is None:
self.adjacencyL...
How do I get the base URL with PHP?
... XAMPP on Windows Vista. In my development, I have http://127.0.0.1/test_website/ .
22 Answers
...
What does the restrict keyword mean in C++?
...h the time.
Edit
I also found that IBM's AIX C/C++ compiler supports the __restrict__ keyword.
g++ also seems to support this as the following program compiles cleanly on g++:
#include <stdio.h>
int foo(int * __restrict__ a, int * __restrict__ b) {
return *a + *b;
}
int main(void) {
...
How can I open multiple files using “with open” in Python?
...ively) you can write
with open('a', 'w') as a, open('b', 'w') as b:
do_something()
In earlier versions of Python, you can sometimes use
contextlib.nested() to nest context managers. This won't work as expected for opening multiples files, though -- see the linked documentation for details.
...
What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
...ract the low-level representation and make it easier to comprehend ( uint64_t instead of long long type, which is 8 bytes).
...
When saving, how can you check if a field has changed?
...
Essentially, you want to override the __init__ method of models.Model so that you keep a copy of the original value. This makes it so that you don't have to do another DB lookup (which is always a good thing).
class Person(models.Model):
name = models.CharF...
Does reading an entire file leave the file handle open?
...file is closed, is this pattern:
with open('Path/to/file', 'r') as content_file:
content = content_file.read()
which will always close the file immediately after the block ends; even if an exception occurs.
Edit: To put a finer point on it:
Other than file.__exit__(), which is "automatical...
What does the “__block” keyword mean?
What exactly does the __block keyword in Objective-C mean? I know it allows you to modify variables within blocks, but I'd like to know...
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