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Can I install Python 3.x and 2.x on the same Windows computer?
I'm running Windows and the shell/OS automatically runs Python based on the registry settings when you run a program on the command line. Will this break if I install a 2.x and 3.x version of Python on the same machine?
...
Displaying the build date
...Info target = null)
{
var filePath = assembly.Location;
const int c_PeHeaderOffset = 60;
const int c_LinkerTimestampOffset = 8;
var buffer = new byte[2048];
using (var stream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
stream.Read(buffer, 0, 2048);
...
Is the order of iterating through std::map known (and guaranteed by the standard)?
...::map is a sorted associative container
std::unordered_map is a hash-table based associative container introduced in C++11
So, in order to clarify the guarantees on ordering.
In C++03:
std::set, std::multiset, std::map and std::multimap are guaranteed to be ordered according to the keys (and th...
How do you create an asynchronous method in C#?
...read calls the asynchronous write method. WriteAsync is implemented by the Base Class Library (BCL), and uses completion ports for its asynchronous I/O. So, the WriteAsync call is passed down to the OS as an asynchronous file write. The OS then communicates with the driver stack, passing along the d...
PostgreSQL Crosstab Query
...m is also limited to exactly three columns in the provided input query: row_name, category, value. There is no room for extra columns like in the 2-parameter alternative below.
Safe form
crosstab(text, text) with 2 input parameters:
SELECT *
FROM crosstab(
'SELECT section, status, ct
FR...
Error Dropping Database (Can't rmdir '.test\', errno: 17)
... a strange file ".empty":
sh-3.2# ls -la data/test
total 0
drwxr-xr-x 3 _mysql wheel 102 Apr 15 12:36 .
drwxr-xr-x 11 _mysql wheel 374 Apr 15 12:28 ..
-rw-r--r-- 1 _mysql wheel 0 Mar 31 10:19 .empty
Once I rm'd the .empty file, the drop database command succeeded.
I don't know whe...
How to fix “Headers already sent” error in PHP
...s Latin-1) or similar "garbage".
In particular graphical editors and Java based IDEs are oblivious to its
presence. They don't visualize it (obliged by the Unicode standard).
Most programmer and console editors however do:
There it's easy to recognize the problem early on. Other editors may iden...
Retrieving the last record in each group - MySQL
... both queries and use the one that is better at performance given your database.
For example, I have a copy of the StackOverflow August data dump. I'll use that for benchmarking. There are 1,114,357 rows in the Posts table. This is running on MySQL 5.0.75 on my Macbook Pro 2.40GHz.
I'll write a...
How to have stored properties in Swift, the same way I had on Objective-C?
...class ObjectAssociation<T: AnyObject> {
private let policy: objc_AssociationPolicy
/// - Parameter policy: An association policy that will be used when linking objects.
public init(policy: objc_AssociationPolicy = .OBJC_ASSOCIATION_RETAIN_NONATOMIC) {
self.policy = polic...
What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
... show you the name of the index, something like this:
CONSTRAINT region_ibfk_1 FOREIGN
KEY (country_id) REFERENCES
country (id) ON DELETE NO
ACTION ON UPDATE NO ACTION
Now simply issue an:
alter table region drop foreign key
region_ibfk_1;
And finally an:
alter table region d...