大约有 40,000 项符合查询结果(耗时:0.0488秒) [XML]

https://stackoverflow.com/ques... 

Lock, mutex, semaphore… what's the difference?

... just one active thread from many others within one process. The other non selected threads (@ acquiring this object) are put to sleep. [No interprocess capability, very primitive object]. 2) Mutex Semaphore (aka Mutex)= Kernel object used for allowing the execution of just one active thread from ...
https://stackoverflow.com/ques... 

Package doesn't exist error in intelliJ

...ing all modules: open File > Project Structure..., go to Modules tab, select all modules and press the remove button, then removing all remaining Maven modules from Maven tool window: select all modules, right click on them, press Remove projects, and then adding them again in Project to...
https://stackoverflow.com/ques... 

When and why are database joins expensive?

...s back to mitigating the size of the working set. Joins involving properly selected keys with correctly set up indexes are cheap, not expensive, because they allow significant pruning of the result before the rows are materialised. Materialising the result involves bulk disk reads which are the mo...
https://stackoverflow.com/ques... 

Test iOS app on device without apple developer program or jailbreak

...ribed in Adding Your Apple ID Account in Xcode. In the project navigator, select the project and your target to display the project editor. Click General and choose your name from the Team pop-up menu. Connect the device to your Mac and choose your device from the Scheme toolbar menu. Below the ...
https://stackoverflow.com/ques... 

How to find the Windows version from the PowerShell command line

...fo. Powershell wrapper: PS C:\> systeminfo /fo csv | ConvertFrom-Csv | select OS*, System*, Hotfix* | Format-List OS Name : Microsoft Windows 7 Enterprise OS Version : 6.1.7601 Service Pack 1 Build 7601 OS Manufacturer : Microsoft Corporation OS Configuration : Stan...
https://stackoverflow.com/ques... 

Some questions about Automatic Reference Counting in iOS5 SDK

... existing code, you can keep using it as is with the -fno-objc-arc you can selectively disable ARC on any file. If you want to disable ARC on MULTIPLE files: Select desired files at Target/Build Phases/Compile Sources in Xcode PRESS ENTER. (double click selects only one file) Type -fno-objc-arc...
https://stackoverflow.com/ques... 

What's wrong with nullable columns in composite primary keys?

...ow in a table: when a table has a primary key, you have a guranteed way to select any row from it. A unique constraint does not necessarily identify every row; it just specifies that if a row has values in its columns, then they must be unique. This is not sufficient to uniquely identify every row...
https://stackoverflow.com/ques... 

How can I make a horizontal ListView in Android? [duplicate]

...d of "HorizontalListView", the "i" is too much) to update child-views when selected. UPDATE: My code that I posted here was wrong I suppose, as I ran into trouble with selection (i think it has to do with view recycling), I have to go back to the drawing board... UPDATE 2: Ok Problem solved, I sim...
https://stackoverflow.com/ques... 

Is there a Pattern Matching Utility like GREP in Windows?

...d on Windows 7/2008R2, optional for XP/2003/Vista/2008) which includes the select-string cmdlet for this purpose. share | improve this answer | follow | ...
https://stackoverflow.com/ques... 

How to get the body's content of an iframe in Javascript?

...getElementById('id_description_iframe'); // or var iframe = document.querySelector('#id_description_iframe'); And then use jQuery's solution var iframeDocument = iframe.contentDocument || iframe.contentWindow.document; It works even in the Internet Explorer which does this trick during the ...