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Does a foreign key automatically create an index?
... I'm just about positive that PostgreSQL creates an index. I'm pretty sure MySQL does. Making the index makes a ton of sense, but IT'T NOT REQUIRED. After all, why reference something if every time the DB goes to look it up it has to do a tablescan?
– MBCook
Ma...
MongoDb query condition on comparing 2 fields
...t those with condition Grade1 > Grade2 , how can I get a query like in MySQL?
4 Answers
...
How to debug a Flask app
...on-dotenv in your virtual environment.
Create a .flaskenv in your project root. By project root, I mean the folder which has your app.py file
Inside this file write the following:
FLASK_APP=myapp
FLASK_ENV=development
Now issue the following command:
flask run
...
How do I make a Git commit in the past?
... your new commit. If you actually want your new file to be added via a new root commit (no parents), then you need something a bit different:
B---C---o---o---o master
git checkout master
git checkout --orphan new-root
git rm -rf .
git add path/to/file
GIT_AUTHOR_DATE='whenever' git commit
git ch...
Getting the PublicKeyToken of .Net assemblies
...Pravat> ([system.reflection.assembly]::loadfile("C:\Program Files (x86)\MySQL\Connector NET 6.6.5\Assemblies\v4.0\MySql.Data.dll")).FullName
like
PS C:\Users\Pravat> ([system.reflection.assembly]::loadfile("dll full path")).FullName
and will appear like
MySql.Data, Version=6.6.5.0, Cu...
.war vs .ear file
...ch as application security role mapping, EJB reference mapping and context root URL mapping of web modules.
Apart from Web modules and EJB modules, EAR files can also contain connector modules packaged as RAR files and Client modules packaged as JAR files.
...
PowerShell script to return versions of .NET Framework on a machine?
...he full version for the 4.x Framework. The earlier answers both return the root number on my system for .NET 3.0 (where the WCF and WPF numbers, which are nested under 3.0, are higher -- I can't explain that), and fail to return anything for 4.0 ...
EDIT: For .Net 4.5 and up, this changed slightly...
App Inventor 2 低功耗蓝牙 BlueToothLE 拓展 · App Inventor 2 中文网
... Disconnect 或 DisconnectWithAddress 引起的，或者在设备移开或重置以致发生连接丢失后引起的。
FloatsReceived – 当从连接的蓝牙设备接收到一个或多个 IEEE 754 浮点值时，将触发该事件。根据上次调用 ReadFloats 或 RegisterForFlo...
Get the current displaying UIViewController on the screen in AppDelegate.m
...
You can use the rootViewController also when your controller is not a UINavigationController:
UIViewController *vc = self.window.rootViewController;
Once you know the root view controller, then it depends on how you have built your UI, bu...
Create subdomains on the fly with .htaccess (PHP)
...ecessary :)
function create_subdomain($subDomain,$cPanelUser,$cPanelPass,$rootDomain) {
// $buildRequest = "/frontend/x3/subdomain/doadddomain.html?rootdomain=" . $rootDomain . "&domain=" . $subDomain;
$buildRequest = "/frontend/x3/subdomain/doadddomain.html?rootdomain=" . $rootDomai...