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Postgres dump of only parts of tables for a dev snapshot
...roduction our database is a few hundred gigabytes in size. For development and testing, we need to create snapshots of this database that are functionally equivalent, but which are only 10 or 20 gigs in size.
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Does R have an assert statement as in python?
a statement that checks if something is true and if not prints a given error message and exits
3 Answers
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How can I limit Parallel.ForEach?
...e a Parallel.ForEach() async loop with which I download some webpages. My bandwidth is limited so I can download only x pages per time but Parallel.ForEach executes whole list of desired webpages.
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Convert Java Array to Iterable
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2nd and 3rd lines are options i would say :)
– fmucar
Apr 26 '12 at 15:37
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NumPy array initialization (fill with identical values)
...th certain values, because it explicitly describes what is being achieved (and it can in principle be very efficient since it performs a very specific task).
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json_encode() escaping forward slashes
...json_encode($str, JSON_UNESCAPED_SLASHES);
If you don't have PHP 5.4 at hand, pick one of the many existing functions and modify them to your needs, e.g. http://snippets.dzone.com/posts/show/7487 (archived copy).
Example Demo
<?php
/*
* Escaping the reverse-solidus character ("/", slash) is ...
Check if null Boolean is true results in exception
...r null as any other object.
In your particular case, your Boolean is null and the if statement triggers an implicit conversion to boolean that produces the NullPointerException. You may need instead:
if(bool != null && bool) { ... }
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How can I rollback a github repository to a specific commit?
...0 commits in it right now. I need to rollback the repository to commit 80, and remove all the subsequent ones.
6 Answers
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Object of custom type as dictionary key
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You need to add 2 methods, note __hash__ and __eq__:
class MyThing:
def __init__(self,name,location,length):
self.name = name
self.location = location
self.length = length
def __hash__(self):
return hash((self.name, self.lo...
Rails create or update magic?
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Rails 6
Rails 6 added an upsert and upsert_all methods that deliver this functionality.
Model.upsert(column_name: value)
[upsert] It does not instantiate any models nor does it trigger Active Record callbacks or validations.
Rails 5, 4, and 3
Not ...