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New transaction is not allowed because there are other threads running in the session LINQ To Entity
...e the ToList method to realise the enumerator into a collection. That will read all items from the enumerator and close the connection to the source, so that you can use the connection for other things.
foreach (var p in pp.ToList())
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Remove all special characters from a string in R?
...ular expressions to identify the unwanted characters. For the most easily readable code, you want the str_replace_all from the stringr package, though gsub from base R works just as well.
The exact regular expression depends upon what you are trying to do. You could just remove those specific cha...
Techniques for Tracing Constraints
... could try GHC's debugging flags, in particular, -ddump-tc-trace, and then read through the resulting log to see where Internal (a -> b) ~ t and (Internal a -> Internal a) ~ t are added to the Wanted set, but that will be quite a long read.
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What does the “@” symbol do in Powershell?
...o initialise arrays. What exactly does the @ symbol denote and where can I read more about it?
5 Answers
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Relational table naming convention [closed]
...eathens. Plural in the table names are a sure sign of someone who has not read any of the standard materials and has no knowledge of database theory.
Some of the wonderful things about Standards are:
they are all integrated with each other
they work together
they were written by minds greater...
“You have mail” message in terminal, os X [closed]
... the /var/mail/<your-username> upon a mail arrival (which is still unread) can trigger You have mail every time you open a new tab in Terminal (which happened to me once). To solve this problem, the file is needed to be removed (ie. sudo rm /var/mail/<your-username>).
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How to choose an AES encryption mode (CBC ECB CTR OCB CFB)?
...ookie on the client side. You will encrypt it of course so the user cannot read and manipulate the data. So what mode should you use? Coming here you read the top answer (sorry for singling you out myforwik). The first one covered - ECB - is not for you, you want to encrypt more than one block, the ...
How to make all Objects in AWS S3 bucket public by default?
...a PHP library to upload a file to my bucket. I have set the ACL to public-read-write and it works fine but the file is still private.
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Python json.loads shows ValueError: Extra data
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You can just read from a file, jsonifying each line as you go:
tweets = []
for line in open('tweets.json', 'r'):
tweets.append(json.loads(line))
This avoids storing intermediate python objects. As long as your write one full tweet...
Why is React's concept of Virtual DOM said to be more performant than dirty model checking?
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I recently read a detailed article about React's diff algorithm here: http://calendar.perfplanet.com/2013/diff/. From what I understand, what makes React fast is:
Batched DOM read/write operations.
Efficient update of sub-tree only.
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