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Display names of all constraints for a table in Oracle SQL
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You need to query the data dictionary, specifically the USER_CONS_COLUMNS view to see the table columns and corresponding constraints:
SELECT *
FROM user_cons_columns
WHERE table_name = '<your table name>';
FYI, unless you specifically created your table with ...
How do you run a Python script as a service in Windows?
...e which provides a higher level interface for operations on these objects, and the other programs to access the objects through that service.
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Where to find Application Loader app in Mac?
I have downloaded applicationloader_1.3.dmg and installed in the destination Macintosh HD.
15 Answers
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[精华]VC++对话框程序打印及打印预览的实现 - C/C++ - 清泛网 - 专注C/C++及内核技术
...应用程序中用MFC应用程序向导在步骤4对话框中选中Print and Print Preview选项，可以包含基本打印及打印预览的支持，应用程序文件菜单中会生成两个菜单项分别是打印（标识符ID_FILE_PRINT）和打印预览(标识符：ID_FILE_PRINT_PREVIEW)，展...
Why use a public method in an internal class?
...presents the key, documented functionality provided by this object."
Basically, my attitude is: suppose I decided to make this internal class into a public class. In order to do that, I want to change exactly one thing: the accessibility of the class. If turning an internal class into a public clas...
Handling applicationDidBecomeActive - “How can a view controller respond to the app becoming Active?
...tionDidBecomeActiveNotification and specify which method that you want to call when that notification gets sent to your application.
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(someMethod:)
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Given a view, how do I get its viewController?
...r, because that would break MVC principles.
The controller, on the other hand, knows which view it's responsible for (self.view = myView), and usually, this view delegates methods/events for handling to the controller.
Typically, instead of a pointer to your view, you should have a pointer to your...
Creating a new empty branch for a new project
...branches departing from the original branch. But now we want to create a small new project to track some documentation. For that we would want to create a new empty branch to start storing our files, and I would want other users of the network to clone that branch.
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How to get the original value of an attribute in Rails
...ibute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should append _before_last_save
Something like:
before_save object
do_something_with object.name_...
Which is faster in Python: x**.5 or math.sqrt(x)?
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I've now run it 3 times on codepad.org and all three times a() was much faster than b().
– Jeremy Ruten
Nov 29 '08 at 1:38
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