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How to declare a variable in MySQL?
... access any user-defined variable without declaring it or
initializing it. If you refer to a variable that has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10; ...
How big should a UIBarButtonItem image be?
...um of about 28 points. (And the HIG should definitely be in your bookmarks if you're working on iOS apps!)
That would translate to images 25px square for older devices like iPad 2 / Mini, 50px square for most current devices like iPhone 8 or iPad, and 75px square for Retina HD devices (the iPhone 6...
Why does PostgreSQL perform sequential scan on indexed column?
...
If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row ...
How to style the option of an html “select” element?
...
This behaviour varies across different browsers and different OSes; it's worth clarifying if you're talking mainly about IE on Windows.
– Vince Bowdren
Apr 19 '13 at 9:10
...
how to add records to has_many :through association in rails
...
@Mischa how should i handle error if House.find(params[:house_id]) is nill.. i got error of TypeMismatch if params[:house_id] is nil.. i already using rescue. but is there any better_way..??
– Vishal
Jul 30 '16 at 10:5...
Clearing a string buffer/builder after loop
...the SB outside is not losing the internal (potentially long) char[] of it. If in the first iterator it grew up enough, the second loop will not need to resize any char[]. But for getting the advantage the "clear method" will have to preserve the size of the internal array. setLength does that but it...
What Product Flavor does Android Studio build by default in build.gradle?
...d Studio as a development tool. When there are several product flavors specified in build.gradle , we notice that Android Studio builds the first one specified alphabetically. Is there a way to tell Android Studio to build and test only a specific product flavor during development?
...
Using “this” with class name
...r class, but since I need to reference the outer class I need a way to signify that.
– skaz
Nov 2 '10 at 18:38
7
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How to get full path of selected file on change of using javascript, jquery-ajax
...er using HTML5 File API, only Firefox provides a mozFullPath property, but if you try to get the value it returns an empty string:
$('input[type=file]').change(function () {
console.log(this.files[0].mozFullPath);
});
http://jsfiddle.net/SCK5A/
So don't waste your time.
edit: If you need th...
JSON.parse vs. eval()
...t using eval() to parse incoming JSON is a bad idea. I'm just wondering if JSON.parse() - which I assume is a part of JavaScript and not a browser-specific function - is more secure.
...