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Multiple INSERT statements vs. single INSERT with multiple VALUES
I'm running a performance comparison between using 1000 INSERT statements:
4 Answers
4...
Transitions on the CSS display property
...rder: 1px solid #eee;
}
div > ul {
visibility: hidden;
opacity: 0;
transition: visibility 0s, opacity 0.5s linear;
}
div:hover > ul {
visibility: visible;
opacity: 1;
}
<div>
<ul>
<li>Item 1</li>
<li>Item 2</li>
<li&...
How do I break out of a loop in Scala?
...f loops.
Suppose you want to sum numbers until the total is greater than 1000. You try
var sum = 0
for (i <- 0 to 1000) sum += i
except you want to stop when (sum > 1000).
What to do? There are several options.
(1a) Use some construct that includes a conditional that you test.
var sum...
JavaScript: Check if mouse button down?
...
150
Regarding Pax' solution: it doesn't work if user clicks more than one button intentionally or ac...
Are tuples more efficient than lists in Python?
...
180
The dis module disassembles the byte code for a function and is useful to see the difference bet...
How do I use valgrind to find memory leaks?
...a Valgrind report that looks like this:
HEAP SUMMARY:
in use at exit: 0 bytes in 0 blocks
total heap usage: 636 allocs, 636 frees, 25,393 bytes allocated
All heap blocks were freed -- no leaks are possible
ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
ERROR SUMMARY: 0 error...
Fill SVG path element with a background-image
...<defs>
<pattern id="img1" patternUnits="userSpaceOnUse" width="100" height="100">
<image href="wall.jpg" x="0" y="0" width="100" height="100" />
</pattern>
</defs>
Adjust the width and height according to your image, then reference it from the path like this:
&...
How to deal with SettingWithCopyWarning in Pandas?
I just upgraded my Pandas from 0.11 to 0.13.0rc1. Now, the application is popping out many new warnings. One of them like this:
...
How to synchronize a static variable among threads running different instances of a class in Java?
...s on the class object.
public class Test {
private static int count = 0;
public static synchronized void incrementCount() {
count++;
}
}
Explicitly synchronize on the class object.
public class Test {
private static int count = 0;
public void incrementCount() {
...
Javascript parseInt() with leading zeros
...
This is because if a number starts with a '0', it's treated as base 8 (octal).
You can force the base by passing the base as the 2nd parameter.
parseInt("09", 10) // 9
According to the docs, the 2nd parameter is optional, but it's not always assumed to be 10, as y...