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Best practice? - Array/Dictionary as a Core Data Entity Attribute [closed]
...into the array or dictionary (it's stored as a BLOB in the data store) and if the collections are large, you may have to move a lot of data to/from the data store (if it's an SQLite data store) just to read or modify a small part of the collection.
The alternative is to use Core Data to-many relati...
Resetting generator object in Python
...p:
print(x)
This could be beneficial from memory usage point of view if the original iteration might not process all the items.
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How to check that an element is in a std::set?
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this is specific for sets and maps. vectors, lists etc. don't have a find member function.
– wilhelmtell
Nov 9 '09 at 13:53
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Why does ContentResolver.requestSync not trigger a sync?
...mber of steps to tell Android that you are capable of synchronizing a specific kind of content using a specific kind of account. It does this in the AndroidManifest.
1. Notify Android that your application package provides syncing
First off, in AndroidManifest.xml, you have to declare that you h...
Getting the parent of a directory in Bash
If I have a file path such as...
11 Answers
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What is the performance cost of having a virtual method in a C++ class?
...od point that a virtual function call may cause an instruction cache miss: if you jump to a code address that is not in cache then the whole program comes to a dead halt while the instructions are fetched from main memory. This is always a significant stall: on Xenon, about 650 cycles (by my tests)....
Safely remove migration In Laravel
...me.php
Reset the composer autoload files: composer dump-autoload
Relax
If you did run the migration (php artisan migrate), you may do this:
a) Run migrate:rollback - it is the right way to undo the last migration (Thnx @Jakobud)
b) If migrate:rollback does not work, do it manually (I remember ...
Using OR in SQLAlchemy
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Note that this approach supports using generators, so if you have a long list of things to OR, you can do filter(or_(User.name == v for v in ('Alice', 'Bob', 'Carl')))
– robru
Aug 26 '15 at 20:21
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How do you rename a Git tag?
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The colon in the push command removes the tag from the remote repository. If you don't do this, Git will create the old tag on your machine when you pull.
Finally, make sure that the other users remove the deleted tag. Please tell them (co-workers) to run the following command:
git pull --prune -...
MongoDB/Mongoose querying at a specific date?
Is it possible to query for a specific date ?
6 Answers
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