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What is more efficient: Dictionary TryGetValue or ContainsKey+Item?
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you can actually look at the .net source for it now too: referencesource.microsoft.com/#mscorlib/system/collections/… you can see that all 3 of TryGetValue, ContainsKey, and this[] call the same FindEntry method and do the same amount of work, only differing in how they...
HTML 5 tag vs Flash video. What are the pros and cons?
...question was made over 9 years ago. It made sense then, it doesn't make it now. Flash is hard on its way out; <video> support is ubiquitous, including mobile devices. Almost anything that Flash could do, HTML can now do too. HTML won, Flash lost. If you're pondering on how to embed video in ...
Changing Java Date one hour back
...lDateTime().minusHours(1)
Java 8: java.time.LocalDateTime
LocalDateTime.now().minusHours(1)
Java 8 java.time.Instant
// always in UTC if not timezone set
Instant.now().minus(1, ChronoUnit.HOURS));
// with timezone, Europe/Berlin for example
Instant.now()
.atZone(ZoneId.of("Europe/Berlin...
MySQL get the date n days ago as a timestamp
...B will do part of it depending on what you want
mysql> SELECT DATE_SUB(NOW(), INTERVAL 30 day);
2009-06-07 21:55:09
mysql> SELECT TIMESTAMP(DATE_SUB(NOW(), INTERVAL 30 day));
2009-06-07 21:55:09
mysql> SELECT UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 30 day));
1244433347
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add created_at and updated_at fields to mongoose schemas
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As of Mongoose 4.0 you can now set a timestamps option on the Schema to have Mongoose handle this for you:
var thingSchema = new Schema({..}, { timestamps: true });
You can change the name of the fields used like so:
var thingSchema = new Schema({....
How to get the day of week and the month of the year?
I don't know much about Javascript, and the other questions I found are related to operations on dates, not only getting the information as I need it.
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Does Python's time.time() return the local or UTC timestamp?
... gives you timestamp. Just remove the milliseconds - str(datetime.datetime.now()).split('.')[0]
– Hussain
Jan 3 '13 at 13:25
17
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How to empty a Heroku database
...e, if you are using SHARED_DATABASE_URL:
$ heroku pg:reset DATABASE_URL
Now to recreate the database with nothing in it:
$ heroku run rake db:migrate
To populate the database with your seed data:
$ heroku run rake db:seed
---OR---
You can combine the last two (migrate & seed) into on...
Reset Entity-Framework Migrations
...ked up my migrations, I used IgnoreChanges on the initial migration, but now I want to delete all my migrations and start with an initial migration with all of the logic.
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Remove large .pack file created by git
... a load of files in to a branch and merged and then had to remove them and now I'm left with a large .pack file that I don't know how to get rid of.
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