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PDO Prepared Inserts multiple rows in single query
...to create the $data array has 28 cols and is about 80,000 lines. The final script took 41s to complete.
Using array_push() to create $insert_values instead of array_merge() resulted in a 100X speed up with execution time of 0.41s.
The problematic array_merge():
$insert_values = array();
foreach(...
Why is require_once so bad to use?
...d, so we are already reaching a point thats noticeable to a human. If that script is called frequently it will cause performance issues on the system. Optimization is not a joke and the whole world is not turning around your PC. There are ten thousands of CPUs in use.
– John
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How to change the default GCC compiler in Ubuntu?
...rnatives --query gcc, which might not work eg in an automated provisioning script. Also, how can this be made platform agnostic?
– ely
Jan 7 at 15:55
add a comment
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What does %~dp0 mean, and how does it work?
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The variable %0 in a batch script is set to the name of the executing batch file.
The ~dp special syntax between the % and the 0 basically says to expand the variable %0 to show the drive letter and path, which gives you the current directory containi...
Allowed characters in Linux environment variable names
...ecial characters as a part of a variable name. However when one program or script (e.g. java or perl) initializes a variable with special characters in its name and calls another executable (a child process) the latter executable can access that variable without problems.
– o...
background function in Python
I've got a Python script that sometimes displays images to the user. The images can, at times, be quite large, and they are reused often. Displaying them is not critical, but displaying the message associated with them is. I've got a function that downloads the image needed and saves it locally. Rig...
Why is parenthesis in print voluntary in Python 2.7?
...SCII is default encoding for Python. But I have at the beginning of Python script #encoding=utf-8, linux env LANG=en_US.UTF-8. So repr encodes not using default ASCII, but utf-8 encoding.
– Karlo Smid
Aug 18 '12 at 9:22
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What does “yield break;” do in C#?
...ar returns in the same method gives a compiler error. Using yield return x alerts the compiler you want this method to be syntactic sugar for creating an Enumerator object. This Enumerator has method MoveNext() and property Current. MoveNext() executes the method until a yield return statement, and ...
Combining node.js and Python
...concurrency as do node.js.
If you feel adventurous, learn clojure (clojurescript, clojure-py) and you'll get the same language that runs and interoperates with existing code on Java, JavaScript (node.js included), CLR and Python. And you get superb marshalling protocol by simply using clojure data ...
How to capture the browser window close event?
...er shut downs its page (synchronously).
<html>
<body>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
<script>
function request() {
return $.ajax({
type: "GET",
url: "http://localhost...