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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...
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...
.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
...
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 ...