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When to use single quotes, double quotes, and backticks in MySQL
...ng query will produce different results (or errors) depending on SQL mode:
SELECT "column" FROM table WHERE foo = "bar"
ANSI_QUOTES disabled
The query will select the string literal "column" where column foo is equal to string "bar"
ANSI_QUOTES enabled
The query will select the column column where ...
What is a method group in C#?
...
Also, if you are using LINQ, you can apparently do something like myList.Select(methodGroup).
So, for example, I have:
private string DoSomethingToMyString(string input)
{
// blah
}
Instead of explicitly stating the variable to be used like this:
public List<string> GetStringStuff()...
Connecting overloaded signals and slots in Qt 5
...alueChanged(QString). From Qt 5.7, there are helper functions provided to select the desired overload, so you can write
connect(spinbox, qOverload<int>(&QSpinBox::valueChanged),
slider, &QSlider::setValue);
For Qt 5.6 and earlier, you need to tell Qt which one you want to p...
Random row from Linq to Sql
...ere row.IsActive // your filter
orderby ctx.Random()
select row).FirstOrDefault();
Note that this is only suitable for small-to-mid-size tables; for huge tables, it will have a performance impact at the server, and it will be more efficient to find the number of rows (Count),...
Overloaded method selection based on the parameter's real type
...
I expect the method selection to take
in consideration the real (not the
declared) parameter type. Am I missing
something?
Yes. Your expectation is wrong. In Java, dynamic method dispatch happens only for the object the method is called ...
Vim multiline editing like in sublimetext?
...d asd asd asd;
Hit <C-v> to enter visual-block mode and expand your selection toward the bottom:
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
asd [a]sd asd asd asd;
Hit I"<Esc> to obtain:
asd...
SQL Server IN vs. EXISTS Performance
...execution operation, to get their results.
An example:
Query 1 ( plan )
select * from dt where dt.customer in (select c.code from customer c where c.active=0)
Query 2 ( plan )
select * from dt where exists (select 1 from customer c where c.code=dt.customer and c.active=0)
...
Why does installing Nokogiri on Mac OS fail with libiconv is missing?
...ed to install xCode command tools to allow you to install libiconv.
xcode-select --install
then install a newer version of libiconv
brew install libiconv
then install your gem
gem install nokogiri -- --with-iconv-dir=/usr/local/Cellar/libiconv/1.14
...
How to detect input type=file “change” for the same file?
I want to fire an event when the user select a file. Doing so with .change event it works if the user changes the file every time.
...
Add directives from directive in AngularJS
...n input tag, but I'd like to make it work for any element, such as divs or selects.
– frapontillo
Oct 9 '13 at 15:37
1
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