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How to calculate “time ago” in Java?
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@Benj - Does it right ? above solution ? because one time is in 12 hour format and another time is in 24 hour format. Let me know your feedback for my query. Thank you in advanced.
– Swift
Dec 15 '16 at 6:50
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Singleton: How should it be used
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Answer:
Use a Singleton if:
You need to have one and only one object of a type in system
Do not use a Singleton if:
You want to save memory
You want to try something new
You want to show off how much you know
Because everyone else is doing it (See cargo cult programme...
The role of #ifdef and #ifndef
...fined" while ifndef means "if the following is not defined".
So:
#define one 0
#ifdef one
printf("one is defined ");
#endif
#ifndef one
printf("one is not defined ");
#endif
is equivalent to:
printf("one is defined ");
since one is defined so the ifdef is true and the ifndef is false....
What's the difference between django OneToOneField and ForeignKey?
What's the difference between Django OneToOneField and ForeignKey ?
9 Answers
9
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Unique BooleanField value in Django?
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Whenever I've needed to accomplish this task, what I've done is override the save method for the model and have it check if any other model has the flag already set (and turn it off).
class Character(models.Model):
name = models.CharField(max_length=255)
is_the_chosen_one ...
One class per file rule in .NET? [closed]
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One class per file also gives you a better idea of what each check in is changing without looking at the diffs of the file.
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How can I make a JPA OneToOne relation lazy
...view was particularly slow. I profiled the view and noticed that there was one query executed by hibernate which took 10 seconds even if there only were two object in the database to fetch. All OneToMany and ManyToMany relations were lazy so that wasn't the problem. When inspecting the actual SQ...
JOIN queries vs multiple queries
...r more tables on different keys, often databases (i.e. mysql) can only use one index per table, meaning maybe one of the joins will be fast (and use an index) whereas the others will be extremely slow. For multiple queries, you can optimize the indexes to use for each query.
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Can I use require(“path”).join to safely concatenate urls?
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It sounds like you want url.resolve. From the Node docs:
url.resolve('/one/two/three', 'four') // '/one/two/four'
url.resolve('http://example.com/', '/one') // 'http://example.com/one'
url.resolve('http://example.com/one', '/two') // 'http://example.com/two'
Edit:
As Andreas corre...
How to express a One-To-Many relationship in Django
...'m defining my Django models right now and I realized that there wasn't a OneToManyField in the model field types. I'm sure there's a way to do this, so I'm not sure what I'm missing. I essentially have something like this:
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