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Django: Why do some model fields clash with each other?
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You have two foreign keys to User. Django automatically creates a reverse relation from User back to GameClaim, which is usually gameclaim_set. However, because you have two FKs, you would have two gameclaim_set attributes, which is obviously impossible. So you need to tell D...
How do I drop table variables in SQL-Server? Should I even do this?
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Table variables are automatically local and automatically dropped -- you don't have to worry about it.
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Handler vs AsyncTask vs Thread [closed]
...so supports reporting progress of the running tasks.
And a Thread is basically the core element of multithreading which a developer can use with the following disadvantage:
If you use Java threads you have to handle the following requirements
in your own code:
Synchronization with the...
@UniqueConstraint and @Column(unique = true) in hibernate annotation
... The same aplies for group.
On the other hand,
@Table(
name = "product_serial_group_mask",
uniqueConstraints = {@UniqueConstraint(columnNames = {"mask", "group"})}
)
Implies that the values of mask + group combined should be unique. That means you can have, for example, a record with mask...
Which is faster: Stack allocation or Heap allocation
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Stack allocation is much faster since all it really does is move the stack pointer.
Using memory pools, you can get comparable performance out of heap allocation, but that comes with a slight added complexity and its own headaches...
Is < faster than
... will not be faster on most architectures. You didn't specify, but on x86, all of the integral comparisons will be typically implemented in two machine instructions:
A test or cmp instruction, which sets EFLAGS
And a Jcc (jump) instruction, depending on the comparison type (and code layout):
jne ...
A html space is showing as %2520 instead of %20
...e using) double encoding characters?
Edit:
Expanding a bit on this, especially for LOCAL links. Assuming you want to link to the resource C:\my path\my file.html:
if you provide a local file path only, the browser is expected to encode and protect all characters given (in the above, you should gi...
Do HTML WebSockets maintain an open connection for each client? Does this scale?
.../HTML requests. However, that doesn't mean WebSockets is a replacement for all uses of AJAX/HTML.
Each TCP connection in itself consumes very little in terms server resources. Often setting up the connection can be expensive but maintaining an idle connection it is almost free. The first limitation...
How to replace a character with a newline in Emacs?
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C-q is really quote-insert which quotes the next character.
– Joe Casadonte
Mar 5 '09 at 2:17
2
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Can PNG image transparency be preserved when using PHP's GDlib imagecopyresampled?
...color($new_size[0],$new_size[1]);
imagecolortransparent($new_im, imagecolorallocate($new_im, 0, 0, 0));
imagecopyresampled($new_im,$im,0,0,0,0,$new_size[0],$new_size[1],$size[0],$size[1]);
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