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Are there disadvantages to using a generic varchar(255) for all text-based fields?
... copied from the storage engine layer to the SQL layer, VARCHAR fields are converted to CHAR to gain the advantage of working with fixed-width rows. So the strings in memory become padded out to the maximum length of your declared VARCHAR column.
When your query implicitly generates a temporary ta...
How do I forward declare an inner class? [duplicate]
...ned first
Create a common base class that can be both used in the function and implemented by the nested class.
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Why is reading lines from stdin much slower in C++ than Python?
I wanted to compare reading lines of string input from stdin using Python and C++ and was shocked to see my C++ code run an order of magnitude slower than the equivalent Python code. Since my C++ is rusty and I'm not yet an expert Pythonista, please tell me if I'm doing something wrong or if I'm mis...
What is the 'dynamic' type in C# 4.0 used for?
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The dynamic keyword is new to C# 4.0, and is used to tell the compiler that a variable's type can change or that it is not known until runtime. Think of it as being able to interact with an Object without having to cast it.
dynamic cust = GetCustomer();
cust.Fir...
Rails update_attributes without save?
...ed, and they are to a degree, but this type of error can easily occur when converting data from an API, or even just using a series of data transformation and forgetting to Hash[] the results of the final .map. Maintain some code 50 lines above and 3 functions removed from your attribute assignment...
How can I get query string values in JavaScript?
.../This doesn't output anything, it just updates the $.QueryString object
//Convert object into string suitable for url a querystring (Requires jQuery)
$.param($.QueryString)
//This outputs something like...
//"param=newvalue&param2=val"
//Update the url/querystring in the browser's location bar...
How do I determine the size of an object in Python?
...be returned if the
object type does not provide means to
retrieve the size and would cause a
TypeError.
getsizeof calls the object’s
__sizeof__ method and adds an additional garbage collector overhead
if the object is managed by the
garbage collector.
See recursive sizeof recipe for an example of ...
How can I add (simple) tracing in C#? [closed]
... application I am writing. Sadly, I can never really remember how it works and would like a tutorial with reference qualities to check up on every now and then. It should include:
...
How to use stringstream to separate comma separated strings [duplicate]
...
Why do you guys always use std:: and full namespaces instead of using namespace? Is there specific reasoning for this? I just always find it as a very noisy and had-to-read syntax.
– Dmitry Gusarov
Oct 14 '19 at 2:45
...
Trusting all certificates using HttpClient over HTTPS
...SSLSocketFactory
itself. Some clues can be found in this post Custom SSL handling stopped working on Android 2.2 FroYo.
An example is like ...
import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;
import java.security.KeyManagementException;
import java.securi...