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In MySQL queries, why use join instead of where?
... Performance Perspective:
Where supported (Oracle 9i+, PostgreSQL 7.2+, MySQL 3.23+, SQL Server 2000+), there is no performance benefit to using either syntax over the other. The optimizer sees them as the same query. But more complex queries can benefit from using ANSI-92 syntax:
Ability to ...
Count with IF condition in MySQL query
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Or even SUM(ccc_news_comments.id = 'approved') as a MySQL-specific trick
– mojuba
Jan 21 '13 at 20:44
1
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Where can I download english dictionary database in a text format? [closed]
... replace the deprecated syntax before running it against a 5.0+ version of MySQL
– Serguei Fedorov
Aug 16 '18 at 2:10
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What's the difference between HEAD^ and HEAD~ in Git?
... / ],
F => [ qw/ I J / ],
);
sub postorder {
my($root,$hash) = @_;
my @parents = @{ $parents{$root} || [] };
postorder($_, $hash) for @parents;
return if $sha1{$root};
@parents = map "-p $sha1{$_}", @parents;
chomp($sha1{$root} = `git commit-tree @parents -m "$roo...
致PHP路上的“年轻人” - PHP - 清泛IT社区,为创新赋能!
...段落的“过来人”,还是想写点东西给“年轻人”。关于如何成长?我直白的答案还是建议通过实践,通过项目来成长。虽然提倡多参加项目,但项目不能是乱七八糟的项目什么都去尝试做,对于刚工作的同学,希望做这两类项...
WAMP/XAMPP is responding very slow over localhost
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This is caused by IPV6. Here is how you make MYSQL not use it. (so, without disabling IPV6)
edit mysql file 'my.ini'
under the [wampmysqld] add the following:
bind-address = ::
Save file and restart mysql service
enjoy!
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How to use php serialize() and unserialize()
...gone through the page u referred. can u please show an example in php, and mysql (if necessary) ?
– Istiaque Ahmed
Dec 27 '11 at 6:52
2
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提升大数据分析思想,拥抱大数据未来 - 资讯 - 清泛网 - 专注C/C++及内核技术
...务和世界范围内产生的数据。而所谓公司的麻烦是指,该如何正确利用这些数据——判断出哪些才是相关的、有用的,哪些是需要过滤掉的。最重要的是,哪些才是有助于推动业务发展的。”
因此,思想转变的第一步应是观察...
How to count total number of watches on a page?
...ange body to html or wherever you put your ng-app)
(function () {
var root = angular.element(document.getElementsByTagName('body'));
var watchers = [];
var f = function (element) {
angular.forEach(['$scope', '$isolateScope'], function (scopeProperty) {
if (element...
MySQL - UPDATE multiple rows with different values in one query
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Excuse my english sir, when i try to make an update mysql give me the error: # 1062 - Duplicate entry 'XXX' for key 'PRIMARY'. That does when I try to update a record with the same value it already had, is there any way to skip the update if the current value is the same as be...