大约有 3,584 项符合查询结果（耗时：0.0490秒） [XML]
Design patterns to avoid [closed]
...drawbacks and some even suggest avoiding the pattern entirely. There's an excellent discussion here . Please direct any comments about the Singleton pattern to that question.
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When should I use a NoSQL database instead of a relational database? Is it okay to use both on the s
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Martin Fowler has an excellent video which gives a good explanation of NoSQL databases. The link goes straight to his reasons to use them, but the whole video contains good information.
You have large amounts of data - especially if you cannot ...
Factors in R: more than an annoyance?
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Factors are an excellent "unique-cases" badging engine. I've recreated this badly many times, and despite a couple of wrinkles occasionally, they are extremely powerful.
library(dplyr)
d <- tibble(x = sample(letters[1:10], 20, replace ...
Can multiple different HTML elements have the same ID if they're different elements?
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Excellent answer. it is always best if you stick to the standards.
– EKanadily
Apr 2 '19 at 10:04
ad...
How do I choose a HTTP status code in REST API for “Not Ready Yet, Try Again Later”? [closed]
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Excellent answer! I wonder why it doesn't have more upvotes.
– lex82
Jun 3 '16 at 8:56
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Actual meaning of 'shell=True' in subprocess
... There are a ton of questions about how to avoid shell=True, many with excellent answers. You happened to pick the one which is about why instead.
– tripleee
Jul 3 '16 at 13:45
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How to validate IP address in Python? [duplicate]
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Excellent idea. The only solution presented until now which works with all IP addresses. >>> from IPy import IP >>> IP("2001:660::1") IP('2001:660::1')
– bortzmeyer
De...
What does @synchronized() do as a singleton method in objective C?
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Excellent answer here:
Help understanding class method returning singleton
with further explanation of the process of creating a singleton.
share
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How to Diff between local uncommitted changes and origin
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Ah, excellent. The key was to leave the master out. I had tried a combination where I was doing a fetch before, but when I did git diff master origin/master it was still comparing against the committed version (obvious in retrosp...
Create Django model or update if exists
...looking for "update if exists else create" use case, please refer to @Zags excellent answer
Django already has a get_or_create, https://docs.djangoproject.com/en/dev/ref/models/querysets/#get-or-create
For you it could be :
id = 'some identifier'
person, created = Person.objects.get_or_create(i...