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How can I tell when a MySQL table was last updated?
... Checksum | Create_options | Comment |
As you can see there is a column called: "Update_time" that shows you the last update time for your_table.
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PowerShell: Setting an environment variable for a single command only
...ariable. But if that is what you need to do you can do it this way:
$env:FOO = 'BAR'; ./myscript
The environment variable $env:FOO can be deleted later like so:
Remove-Item Env:\FOO
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How can I add an item to a IEnumerable collection?
...s can be added. In fact, it does not necessarily represent a collection at all! For example:
IEnumerable<string> ReadLines()
{
string s;
do
{
s = Console.ReadLine();
yield return s;
} while (!string.IsNullOrEmpty(s));
}
IEnumerable<string> lines ...
How to add column if not exists on PostgreSQL?
...UE;
END;
$BODY$
LANGUAGE 'plpgsql';
usage:
select add_column('public', 'foo', 'bar', 'varchar(30)');
In Python how should I test if a variable is None, True or False
...
a = 'foo' if a: print 'its true' a is not actually TRUE, it's just not none
– wesm
Apr 3 '15 at 21:06
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Explicitly calling a default method in Java
...s per this article you access default method in interface A using
A.super.foo();
This could be used as follows (assuming interfaces A and C both have default methods foo())
public class ChildClass implements A, C {
@Override
public void foo() {
//you could completely override ...
What are static factory methods?
... a factory method, you would simply call the class's constructor directly: Foo x = new Foo(). With this pattern, you would instead call the factory method: Foo x = Foo.create(). The constructors are marked private, so they cannot be called except from inside the class, and the factory method is m...
Detecting an undefined object property
...is the special value `undefined`");
}
To check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associated with an i...
How to create enum like type in TypeScript?
...elease) you can use the enum definition like this:
enum TShirtSize {
Small,
Medium,
Large
}
var mySize = TShirtSize.Large;
By default, these enumerations will be assigned 0, 1 and 2 respectively. If you want to explicitly set these numbers, you can do so as part of the enum declaration....
what is the best way to convert a json formatted key value pair to ruby hash with symbol as key?
... string key
}
}
Method 1: JSON.parse - symbolizes all keys recursively => Does not preserve original mix
JSON.parse( h.to_json, {:symbolize_names => true} )
=> { :youtube => { :search=> "daffy", :history => ["goofy", "mickey"] } }
Method 2: ActiveSup...