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add column to mysql table if it does not exist
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OK this is really crude but someone's got to say it. if you are simply running a SQL script from the command line, you can give mysql the --force switch, which means keep going even if there's an error. then, just go for it. you just want...
What is the proper way to re-attach detached objects in Hibernate?
...e to the DB,
and overwrite any intervening updates.
refresh() cannot be called on a detached entity.
lock() cannot be called on a detached entity,
and even if it could, and it did reattach the entity,
calling 'lock' with argument 'LockMode.NONE'
implying that you are locking, but not locking,
i...
How to set selected value of jquery select2?
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To dynamically set the "selected" value of a Select2 component:
$('#inputID').select2('data', {id: 100, a_key: 'Lorem Ipsum'});
Where the second parameter is an object with expected values.
UPDATE:
This does work, just wanted to n...
SQL is null and = null [duplicate]
... 1), (1, 1);
select 'x = null' as test , x, y from t where x = null
union all
select 'x != null', x, y from t where x != null
union all
select 'not (x = null)', x, y from t where not (x = null)
union all
select 'x = y', x, y from t where x = y
union all
select 'not (x = y)', x, y from t where not (...
What is the purpose of willSet and didSet in Swift?
... for instance to notify other objects that the property just changed. When all you have is get/set, you need another field to hold the value. With willSet and didSet, you can take action when the value is modified without needing another field. For instance, in that example:
class Foo {
var myP...
What does pylint's “Too few public methods” message mean
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The error basically says that classes aren't meant to just store data, as you're basically treating the class as a dictionary. Classes should have at least a few methods to operate on the data that they hold.
If your class looks like this:...
How to request Administrator access inside a batch file
...s method doesn't forward arguments. Do you know How that can be done? Basically what I observe is that on the first line %1 has some value and on the last line %1 is null. I need to forward the arguments.
– prongs
Jan 11 '13 at 11:54
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Can I use Objective-C blocks as properties?
... @CharlieMonroe - Yes you are probably right, but dont you need a dealloc implementation to nil or release the block property without ARC? (its been a while since I used non-ARC)
– Robert
Mar 31 '13 at 21:58
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Python string class like StringBuilder in C#?
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There is no one-to-one correlation. For a really good article please see Efficient String Concatenation in Python:
Building long strings in the Python
progamming language can sometimes
result in very slow running code. In
this article I investigate the
comp...
How to get the request parameters in Symfony 2?
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The naming is not all that intuitive:
use Symfony\Component\HttpFoundation\Request;
public function updateAction(Request $request)
{
// $_GET parameters
$request->query->get('name');
// $_POST parameters
$request->r...