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Difference between Key, Primary Key, Unique Key and Index in MySQL
...would use indexes to improve the speed of data retrieval. An index is typically created on columns used in JOIN, WHERE, and ORDER BY clauses.
Imagine you have a table called users and you want to search for all the users which have the last name 'Smith'. Without an index, the database would have t...
Set cursor position on contentEditable
... range.collapse();
range.insertNode(cursorEnd);
}
};
// Add callbacks to afterFocus to be called after cursor is replaced
// if you like, this would be useful for styling buttons and so on
var afterFocus = [];
editable.onfocus = function(e) {
// Slight delay will avoid the initial ...
Search for a string in Enum and return the Enum
...
@user1531040 Actually, there is an Enum.TryParse.
– DarLom
Nov 1 '17 at 21:14
...
isset() and empty() - what to use
... check - is variable empty or contains something. To solve this task, I usually do the following.
6 Answers
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Working with time DURATION, not time of day
... cell B2 and drag as far down as the A column goes to apply the formula to all data in col A.
Last step, be sure to highlight all of column B and set it to Number format (the application of the formula may have automatically set format to Time).
...
What is the most frequent concurrency issue you've encountered in Java? [closed]
...are not synchronized this is not guaranteed to work. This mistake is especially devilish as in 99.999% it won't matter in practice as the reader thread will eventually see the change - but we don't know how soon he saw it.
s...
Use of .apply() with 'new' operator. Is this possible?
...CMAScript5's Function.prototype.bind things get pretty clean:
function newCall(Cls) {
return new (Function.prototype.bind.apply(Cls, arguments));
// or even
// return new (Cls.bind.apply(Cls, arguments));
// if you know that Cls.bind has not been overwritten
}
It can be used as foll...
Delete fork dependency of a GitHub repository
How can I make GitHub forget or disassociate that my repo was originally a fork of another project?
6 Answers
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How do I measure request and response times at once using cURL?
...me="curl -w \"@$HOME/.curl-format.txt\" -o NUL -s "
Then you can simply call...
curltime wordpress.org
Thanks to commenter Pete Doyle!
Make a Linux/Mac stand-alone script
This script does not require a separate .txt file to contain the formatting.
Create a new file, curltime, somewhere in ...
What are the best practices for using a GUID as a primary key, specifically regarding performance?
I have an application that uses GUID as the Primary Key in almost all tables and I have read that there are issues about performance when using GUID as Primary Key. Honestly, I haven't seen any problem, but I'm about to start a new application and I still want to use the GUIDs as the Primary Keys, b...