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What does the exclamation mark do before the function?
...iling semicolon, and yet that will give the flexibility to put them in any order with no worry.
!function abc(){}();
!function bca(){}();
Will work the same as
!function abc(){}();
(function bca(){})();
but saves one character and arbitrary looks better.
And by the way any of +,-,~,void opera...
Referring to a Column Alias in a WHERE Clause
...e the WHERE clause. This is usually done with parenthesis to force logical order of operation or with a Common Table Expression (CTE):
Parenthesis/Subselect:
SELECT
*
FROM
(
SELECT
logcount, logUserID, maxlogtm,
DATEDIFF(day, maxlogtm, GETDATE()) AS daysdiff
FROM statslogsumma...
Rename MySQL database [duplicate]
...atabase with the database name you wanted.
The short, quick steps without all the above explanation are:
mysqldump -u root -p original_database > original_database.sql
mysql -u root -p -e "create database my_new_database"
mysql -u root -p my_new_database < original_database.sql
mysql -u roo...
How do I declare a namespace in JavaScript?
...o safely add to the same namespace when they don't know in advance in what order they will execute. This can be helpful either if you want to be able to reorder your script inclusions arbitrarily without breaking your code, or if you want to load scripts asynchronously with the async attribute and s...
Get nth character of a string in Swift programming language
...ng a linear loop inside another linear loop means this for loop is accidentally O(n2) — as the length of the string increases, the time this loop takes increases quadratically. Instead of doing that you could use the characters's string collection.
– ignaciohugog
...
How are “mvn clean package” and “mvn clean install” different?
... any of the lifecycle phases, it executes each default life cycle phase in order, before executing the command itself.
order of execution
validate >> compile >> test (optional) >> package >> verify >> install >> deploy
So when you run the command mvn packag...
Regular expression to find URLs within a string
...
It's 2017, and unicode domain names are all over the place. \w may not match international symbols (depends on regex engine), the range is needed instead: a-zA-Z0-9\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF.
– Michael Antipin
Aug...
What is offsetHeight, clientHeight, scrollHeight?
...ent in pixels, including padding but not the horizontal scrollbar height, border, or margin
offsetHeight:
is a measurement which includes the element borders, the element vertical padding, the element horizontal scrollbar (if present, if rendered) and the element CSS height.
scrollHeight:
...
SQL left join vs multiple tables on FROM line?
... Employee.DepartmentID
Note that the last one there is an inner join, in order to fulfill the criteria that you only want departments with people.
Ok, so what happens now. Well, the problem is, it depends on the database engine, the query optimizer, indexes, and table statistics. Let me explain.
...
What are valid values for the id attribute in HTML?
...
For HTML 4, the answer is technically:
ID and NAME tokens must begin with a letter ([A-Za-z]) and may be followed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").
HTML 5 is even more permissiv...