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Difference between Destroy and Delete
...llbacks on the model while delete doesn't.
From the Rails API:
ActiveRecord::Persistence.delete
Deletes the record in the database and freezes this instance to reflect that no changes should be made (since they can't be persisted). Returns the frozen instance.
The row is simply removed w...
Cache Invalidation — Is there a General Solution?
...gh then you either:
accept that you sometime operate with out of date information and do not always check b
do your level best to make checking b as fast as possible
You cannot have your cake and eat it...
If you can layer an additional cache based on a over the top then this affects the initia...
json.dumps vs flask.jsonify
...t that already has the appropriate content-type header 'application/json' for use with json responses. Whereas, the json.dumps() method will just return an encoded string, which would require manually adding the MIME type header.
See more about the jsonify() function here for full reference.
Edit:...
git: undo all working dir changes including new files
How to delete all changes from working directory including new untracked files. I know that git checkout -f does that, but it doesn't delete new untracked files created since last commit.
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Does Java casting introduce overhead? Why?
Is there any overhead when we cast objects of one type to another? Or the compiler just resolves everything and there is no cost at run time?
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What does set -e mean in a bash script?
...'m studying the content of this preinst file that the script executes before that package is unpacked from its Debian archive (.deb) file.
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libxml install error using pip
This is my error:
28 Answers
28
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What is the difference between JDK and JRE?
...new programs.
The JDK is the Java Development Kit, the full-featured SDK for Java. It has everything the JRE has, but also the compiler (javac) and tools (like javadoc and jdb). It is capable of creating and compiling programs.
Usually, if you only care about running Java programs on computer you ...
Unzip files programmatically in .net
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I tried using SharpZipLib and it worked fine. I guess I'll have to see if the prohibition against third party libs and apss is a strict rule or more of a guidline.
– Petteri
May 7 '09 at 21:49
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Difference between HashMap, LinkedHashMap and TreeMap
...ent the Map interface and offer mostly the same functionality. The most important difference is the order in which iteration through the entries will happen:
HashMap makes absolutely no guarantees about the iteration order. It can (and will) even change completely when new elements are added.
Tree...