大约有 40,000 项符合查询结果（耗时：0.0303秒） [XML]
How to 'bulk update' with Django?
...ings like incrementing rows:
from django.db.models import F
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
See the documentation.
However, note that:
This won't use ModelClass.save method (so if you have some logic inside it won't be triggered).
No django signals will be emitte...
Different bash prompt for different vi editing mode?
...e-in-prompt on
into /etc/inputrc or ~/.inputrc (thx stooj) should affect all your readline-enabled programs ;)
share
|
improve this answer
|
follow
|
...
Define make variable at rule execution time
...r are evaluated. In order to create the directory only when out.tar is actually fired, you need to move the directory creation down into the steps:
out.tar :
$(eval TMP := $(shell mktemp -d))
@echo hi $(TMP)/hi.txt
tar -C $(TMP) cf $@ .
rm -rf $(TMP)
The eval function evaluates a...
How can I hash a password in Java?
...
You can actually use a facility built in to the Java runtime to do this. The SunJCE in Java 6 supports PBKDF2, which is a good algorithm to use for password hashing.
byte[] salt = new byte[16];
random.nextBytes(salt);
KeySpec spec = new...
what is .netrwhist?
...riting files across networks. .netrwhist is a history file which maintains all the directories that were modified. So whenever you modify the contents of ~/.vim it adds one entry in .netrwhist
A sample .netrwhist is as shown
let g:netrw_dirhistmax =10
let g:netrw_dirhist_cnt =6
let g:netrw_dirhis...
Finding all possible combinations of numbers to reach a given sum
How would you go about testing all possible combinations of additions from a given set N of numbers so they add up to a given final number?
...
Underscore: sortBy() based on multiple attributes
... said, that's pretty hacky. To do this properly you'd probably want to actually use the core JavaScript sort method:
patients.sort(function(x, y) {
var roomX = x[0].roomNumber;
var roomY = y[0].roomNumber;
if (roomX !== roomY) {
return compare(roomX, roomY);
}
return compare(x[0].name...
How do I loop through or enumerate a JavaScript object?
...uilt-in key-value pairs that have meta-information. When you loop through all the key-value pairs for an object you're looping through them too. hasOwnPropery() filters these out.
– danieltalsky
Jan 27 '12 at 15:56
...
A proper wrapper for console.log with correct line number?
...
This is an old question and All the answers provided are overly hackey, have MAJOR cross browser issues, and don't provide anything super useful. This solution works in every browser and reports all console data exactly as it should. No hacks required...
Using OR in SQLAlchemy
...
329
SQLAlchemy overloads the bitwise operators &, | and ~ so instead of the ugly and hard-to-r...