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What is the simplest SQL Query to find the second largest value?
... produce the correct second largest value while if you used the top 2 desc and min approach, you may get the largest value instead.
– Pankaj Sharma
Apr 1 '13 at 19:22
...
Getting an “ambiguous redirect” error
...
Bash can be pretty obtuse sometimes.
The following commands all return different error messages for basically the same error:
$ echo hello >
bash: syntax error near unexpected token `newline`
$ echo hello > ${NONEXISTENT}
bash: ${NONEXISTENT}: ambiguous redirect
$ echo h...
Prevent body scrolling but allow overlay scrolling
... when you open the overlay a noscroll class is applied to the body element and overflow: hidden is set, thus body is no longer scrollable.
The overlay (created on-the-fly or already inside the page and made visible via display: block, it makes no difference) has position : fixed and overflow-y: scr...
How do I make JavaScript beep?
...directly in JavaScript. You'll need to embed a short WAV file in the HTML, and then play that via code.
An Example:
<script>
function PlaySound(soundObj) {
var sound = document.getElementById(soundObj);
sound.Play();
}
</script>
<embed src="success.wav" autostart="false" width=...
What does the “===” operator do in Ruby? [duplicate]
...so equal to a. Also, one would expect equality to be transitive: if a == b and b == c, then a == c. While there is no way to actually guarantee that in a single-dispatch language like Ruby, you should at least make an effort to preserve this property (for example, by following the coerce protocol).
...
Java's final vs. C++'s const
...even in Java: a has already been assigned a value.
}
}
In both Java and C++ member variables may be final/const respectively. These need to be given a value by the time an instance of the class is finished being constructed.
In Java they must be set before the constructor has finished, this ...
JavaScript: how to change form action attribute value based on selection?
...
Simple and easy in javascipt
<script>
document.getElementById("selectsearch").addEventListener("change", function(){
var get_form = document.getElementById("search-form") // get form
get_form.action = '/search/' ...
Do I need elements in persistence.xml?
...="OrderManagement">
<description>This unit manages orders and customers.
It does not rely on any vendor-specific features and can
therefore be deployed to any persistence provider.
</description>
<jta-data-source>jdbc/MyOrderDB<...
How to create a directory using Ansible
... @Alex all immediate subdirectories is confusing, could you define that and give an example?
– Jamie Jackson
Sep 13 '18 at 20:34
...
Building executable jar with maven?
...6: someone fixed it, this answer refers to the version preceding the edit) and this explains, at least partially, why you run into troubles.
It generates two jar files in logmanager/target: logmanager-0.1.0.jar, and logmanager-0.1.0-jar-with-dependencies.jar.
The first one is the JAR of the logma...