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Display names of all constraints for a table in Oracle SQL
...
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 ...
What are five things you hate about your favorite language? [closed]
...ld be matched to another NULL value. If you understand this (what also is called ternary logic) than you might understand the reason for introducing the "IS" operator for testing against NULL.
– Alex
Aug 26 '10 at 16:58
...
window.onload vs
...load is less obtrusive though - it takes your JavaScript out of the HTML.
All of the common JavaScript libraries, Prototype, ExtJS, Dojo, JQuery, YUI, etc. provide nice wrappers around events that occur as the document is loaded. You can listen for the window onLoad event, and react to that, but on...
Google Guava isNullOrEmpty for collections
...eyard."
We don't believe that "is null or empty" is a question you ever really want to be asking about a collection.
If a collection might be null, and null should be treated the same as empty, then get all that ambiguity out of the way up front, like this:
Set<Foo> foos = NaughtyClass.getF...
How can I use xargs to copy files that have spaces and quotes in their names?
...
You can combine all of that into a single find command:
find . -iname "*foobar*" -exec cp -- "{}" ~/foo/bar \;
This will handle filenames and directories with spaces in them. You can use -name to get case-sensitive results.
Note: The ...
Why should I prefer to use member initialization lists?
...tyle. For class members which are classes, then it avoids an unnecessary call to a default constructor. Consider:
class A
{
public:
A() { x = 0; }
A(int x_) { x = x_; }
int x;
};
class B
{
public:
B()
{
a.x = 3;
}
private:
A a;
};
In this case, the construct...
How do you count the lines of code in a Visual Studio solution?
...x", "Cyclomatic Complexity", "Depth of Inheritance", and "Class Coupling", all of which are pretty complicated to compute, and you can't run the metrics for just part of it. What this means is that if your code-base is particularly large, you might be sitting for hours waiting for it. If all you w...
In Python, how do I index a list with another list?
...ng, either by integer, slice or index-list:
class Flexlist(list):
def __getitem__(self, keys):
if isinstance(keys, (int, slice)): return list.__getitem__(self, keys)
return [self[k] for k in keys]
Which, for your example, you would use as:
L = Flexlist(['a', 'b', 'c', 'd', 'e...
Get element inside element by class and ID - JavaScript
...er than worrying about browser compatibility yourself (let someone else do all the work). If you want just a library to do that, then Sizzle will work great. In Sizzle, this would be be done like this:
Sizzle("#foo .bar")[0].innerHTML = "Goodbye world!";
jQuery has the Sizzle library built-in...
How to comment and uncomment blocks of code in the Office VBA Editor
...ndy - I can't believe I'd never found it before. A shortcut key would be really handy but unfortunately that doesn't seem to exist.
– Jamie Bull
Oct 17 '12 at 12:26
3
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