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Why are dates calculated from January 1st, 1970?
...1st, 1970) as default standard
The Question makes two false assumptions:
All time-tracking in computing is done as a count-since-1970.
Such tracking is standard.
Two Dozen Epochs
Time in computing is not always tracked from the beginning of 1970 UTC. While that epoch reference is popular, various...
.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included i
I have this error when trying to browse php files locally
8 Answers
8
...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...languages or characters.
On modern servers, this performance boost will be all but negligible. It was devised in a time when servers had a tiny fraction of the CPU performance of today's computers.
Benefits of utf8mb4_unicode_ci over utf8mb4_general_ci
utf8mb4_unicode_ci, which uses the Unicode r...
Perform .join on value in array of objects
...Array.prototype.map is what you're looking for if you want to code functionally.
[
{name: "Joe", age: 22},
{name: "Kevin", age: 24},
{name: "Peter", age: 21}
].map(function(elem){
return elem.name;
}).join(",");
In modern JavaScript:
[
{name: "Joe", age: 22},
{name: "Kevin", age: 2...
What is the difference between statically typed and dynamically typed languages?
I hear a lot that new programming languages are dynamically typed but what does it actually mean when we say a language is dynamically typed vs. statically typed?
...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...:
SET @rUsername = ‘aname’ COLLATE utf8_unicode_ci; -- COLLATE added
CALL updateProductUsers(@rUsername, @rProductID, @rPerm);
Option 2: add COLLATE to the WHERE clause:
CREATE PROCEDURE updateProductUsers(
IN rUsername VARCHAR(24),
IN rProductID INT UNSIGNED,
IN rPerm VARCHAR(16...
How can I check a C# variable is an empty string “” or null? [duplicate]
...
@Lion Liu: Actually I think PHP has exactly as much to offer. See: php.net/manual/en/function.empty.php
– Milan
Feb 2 '16 at 20:09
...
counting number of directories in a specific directory
... can instead test the directory's children and do not descend into them at all:
$ find .vim/* -maxdepth 0 -type d
.vim/after
.vim/autoload
.vim/bundle
.vim/colors
.vim/compiler
.vim/doc
.vim/ftdetect
.vim/ftplugin
.vim/indent
.vim/plugin
.vim/syntax
$ find .vim/* -maxdepth 0 -type d | wc -l
11
$ f...
【App Inventor 2 数据可视化】使用柱状图和饼图收集数据 - App应用开发 - ...
...理解。帮助人们一眼就能看到他们在生活或社区中关心的问题发生了什么。你喜欢用哪些不同方式的图像和图形来理解数据?所有的数据都留在App中，直到你按下Reset按钮。在本系列中，你可以查看以下指南，了解如何将数据发送...
Nginx no-www to www and www to no-www
...n.php last;
# etc etc...
}
}
Note: I have not originally included https:// in my solution since we use loadbalancers and our https:// server is a high-traffic SSL payment server: we do not mix https:// and http://.
To check the nginx version, use nginx -v.
Strip www from ...