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#1071 - Specified key was too long; max key length is 1000 bytes
...ing such long VARCHAR columns anyway, because the index will be very bulky and inefficient.
The best practice is to use prefix indexes so you're only indexing a left substring of the data. Most of your data will be a lot shorter than 255 characters anyway.
You can declare a prefix length per colu...
Is it possible to print a variable's type in standard C++?
... update to a very old question: Print variable type in C++.
The accepted (and good) answer is to use typeid(a).name(), where a is a variable name.
Now in C++11 we have decltype(x), which can turn an expression into a type. And decltype() comes with its own set of very interesting rules. For exam...
Saving an Object (Data persistence)
...
You could use the pickle module in the standard library.
Here's an elementary application of it to your example:
import pickle
class Company(object):
def __init__(self, name, value):
self.name = name
self.value = value
with open('company_data....
Internet Explorer 11 detection
...t && !!document.documentMode;
// true on IE11
// false on Edge and other IEs/browsers.
Original Answer
In order to check Ie11 , you can use this : ( tested)
(or run this)
!(window.ActiveXObject) && "ActiveXObject" in window
I have all VMS of IE :
Notice : this w...
How can I make an EXE file from a Python program? [duplicate]
...A .py to .exe converter using a simple graphical interface built using Eel and PyInstaller in Python.
py2exe is probably what you want, but it only works on Windows.
PyInstaller works on Windows and Linux.
Py2app works on the Mac.
...
Cleaner way to update nested structures
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Zippers
Huet's Zipper provides convenient traversal and 'mutation' of an immutable data structure. Scalaz provides Zippers for Stream (scalaz.Zipper), and Tree (scalaz.TreeLoc). It turns out that the structure of the zipper is automatically derivable from the original data str...
Git - Undo pushed commits
...in a remote repository, synchronized with a local repository (development) and the server one (prod). I've been making some commited changes already pushed to remote and pulled from the server. Now, I want to undo those changes. So I could just git checkout to the commit before the changes and com...
How does the HyperLogLog algorithm work?
I've been learning about different algorithms in my spare time recently, and one that I came across which appears to be very interesting is called the HyperLogLog algorithm - which estimates how many unique items are in a list.
...
What does “abstract over” mean?
...ala literature, I encounter the phrase "abstract over", but I don't understand the intent. For example , Martin Odersky writes
...
What are the relationships between Any, AnyVal, AnyRef, Object and how do they map when used in Java
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I'll disagree with Chris's answer in one regard. The classes Any, AnyRef and AnyVal are classes. But they don't appear as classes in bytecode, because of intrinsic limitations of the JVM.
This arises out of the fact that not everything in Java is an object. In addition to objects, there are primi...