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Count(*) vs Count(1) - SQL Server
...not the case for Oracle or most other modern RDBMS but is the case for old MySQL's storage engine, MyISAM), then COUNT(*) would just need to take the value from the metadata.
– Quassnoi
Oct 31 '18 at 18:29
...
AngularJS access parent scope from child controller
...other controllers, you can install a "hook" to the global scope:
function RootCtrl($scope) {
$scope.root = $scope;
}
Then in any child controller, you can access the "global" scope with $scope.root. Anything you set here will be globally visible.
Example:
function RootCtrl($scope) {
...
logger configuration to log to file and print to stdout
...
Just get a handle to the root logger and add the StreamHandler. The StreamHandler writes to stderr. Not sure if you really need stdout over stderr, but this is what I use when I setup the Python logger and I also add the FileHandler as well. Then all...
tinyxml XML解析库下载（tinyxml2.h 和 tinyxml2.cpp） - 源码下载 - 清泛...
...int SIZE >
class MemPoolT : public MemPool
{
public:
MemPoolT() : _root(0), _currentAllocs(0), _nAllocs(0), _maxAllocs(0), _nUntracked(0) {}
~MemPoolT() {
// Delete the blocks.
for( int i=0; i<_blockPtrs.Size(); ++i ) {
delete _blockPtrs[i];
}
...
What's the right way to pass form element state to sibling/parent elements?
...ectly, your first solution is suggesting that you're keeping state in your root component? I can't speak for the creators of React, but generally, I find this to be a proper solution.
Maintaining state is one of the reasons (at least I think) that React was created. If you've ever implemented your...
两大桌面系统之战：Yosemite vs Windows 10 - 操作系统(内核) - 清泛网 - ...
... 的主要对比，OS X Yosemite 向我们证明了一个操作系统应该如何演变进化，至于 Windows 10 最好的评价或许只能说，和上一代相比没有那么糟糕了。不知道各位读者有怎样的看法？Yosemite,Win10,OS X
实现一个简单的服务端推方案 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...味着简陋，轮询数据库是不可以接受的，下面我们来看看如何解决这个问题。在这里我们放弃了传统的LAMP技术，转而使用Nginx与Lua来实现。
Modified Long Polling
此方案的主要思路是这样的：使用Nginx作为服务端，通过Lua协程来...
MIN/MAX vs ORDER BY and LIMIT
...OM `tbl`;
Simply because it is ANSI compatible. Limit 1 is particular to MySql as TOP is to SQL Server.
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Multiple columns index when using the declarative ORM extension of sqlalchemy
...f you have a dictionary for table_args like I currently do? table_args = {'mysql_engine':'InnoDB'}
– Nick Holden
Sep 1 '11 at 8:39
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创建增量同步Oracle物化视图问题 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...from t_mv_test@dblink_name;
这样，不管数据库A上的此表的主键如何变化，我一概不管。但是，有时必须要使用with primary key，例如跨库跨平台时。
物化视图对应的表上没有主键，如果需要索引可以另行添加。
最后小结一下，这个...