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Difference between Destroy and Delete
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Basically destroy runs any callbacks on the model while delete doesn't.
From the Rails API:
ActiveRecord::Persistence.delete
Deletes the record in the database and freezes this instance to reflect that no changes should be ...
How to generate a random int in C?
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Note: Don't use rand() for security. If you need a cryptographically secure number, see this answer instead.
#include <time.h>
#include <stdlib.h>
srand(time(NULL)); // Initialization, should only be called once.
int r = rand(); // Returns a pseudo-random integer bet...
MySQL “WITH” clause
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Update: MySQL 8.0 is finally getting the feature of common table expressions, including recursive CTEs.
Here's a blog announcing it: http://mysqlserverteam.com/mysql-8-0-labs-recursive-common-table-expressions-in-mysql-ctes/
Below is my earlier answ...
What does the smiley face “:)” mean in CSS?
...wsers.
Also there's a hack for <= IE 8:
div {
color: blue; /* All browsers */
color: purple\9; /* IE8 and earlier */
*color: pink; /* IE7 and earlier */
}
However that's not a good idea, they don't validate. You always feel free to work with Conditional comments for targeting...
Nginx reverse proxy causing 504 Gateway Timeout
...nd it had to do with not using a keep-alive on the connection. I can't actually answer why this is but, in clearing the connection header I solved this issue and the request was proxied just fine:
server {
location / {
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header ...
Python: How to create a unique file name?
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I didn't think your question was very clear, but if all you need is a unique file name...
import uuid
unique_filename = str(uuid.uuid4())
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How to best display in Terminal a MySQL SELECT returning too many fields?
... Db: mydatabase1
User: myuser1
Select_priv: Y
Insert_priv: Y
Update_priv: Y
...
*************************** 2. row ***************************
Host: localhost
Db: mydatabase2
User...
How do I get the type of a variable?
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I totally disagree. Java, C#, PHP, Perl, Python and so on were designed in C and C++ and they are not caterpillars. (When you create an database application to open variable tables from 'unknown' databases you need to control fiel...
Center content of UIScrollView when smaller
... the scroll view, everything works fine. However, when the image becomes smaller than the scroll view, it sticks to the top left corner of the scroll view. I would like to keep it centered, like the Photos app.
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filtering NSArray into a new NSArray in Objective-C
... edited Jan 17 '18 at 6:45
Niall Kiddle
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answered Sep 21 '08 at 5:43
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