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pandas: multiple conditions while indexing data frame - unexpected behavior
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As you can see, the AND operator drops every row in which at least one
value equals -1. On the other hand, the OR operator requires both
values to be equal to -1 to drop them.
That's right. Remember that you're writing the condition in te...
Using OR in SQLAlchemy
I've looked through the docs and I cant seem to find out how to do an OR query in SQLAlchemy. I just want to do this query.
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SHA1 vs md5 vs SHA256: which to use for a PHP login?
I'm making a php login, and I'm trying to decide whether to use SHA1 or Md5, or SHA256 which I read about in another stackoverflow article. Are any of them more secure than others? For SHA1/256, do I still use a salt?
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Table Naming Dilemma: Singular vs. Plural Names [closed]
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Others have given pretty good answers as far as "standards" go, but I just wanted to add this... Is it possible that "User" (or "Users") is not actually a full description of the data held in the table? Not that you should get too crazy with table names and specificity, but p...
Django filter versus get for single object?
...lly implemented in Django, so there should be no "performance" difference (and the fact that you're thinking about it indicates you're violating one of the cardinal rules of programming, namely trying to optimize code before it's even been written and profiled -- until you have the code and can run ...
Difference between static and shared libraries?
What is the difference between static and shared libraries?
8 Answers
8
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Test iOS app on device without apple developer program or jailbreak
... has finally introduced a new feature in Xcode 7 that allows you to deploy and run any number of apps on any of your devices, simply by logging in with your Apple ID. You will no longer need a paid Program membership to deploy apps on your own device (and you certainly no longer have to jailbreak yo...
How to install Android SDK Build Tools on the command line?
I want to setup the Android dev environment from command line, and encounter the following issue:
19 Answers
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PDOException SQLSTATE[HY000] [2002] No such file or directory
...basic) site to fortrabbit, but as soon as I connect to SSH to run some commands (such as php artisan migrate or php artisan db:seed ) I get an error message:
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How to use php serialize() and unserialize()
... means to put the structure into a "lower common denominator" that can be handled by things other than PHP, like databases, text files, sockets. The standard PHP function serialize is just a format to express such a thing, it serializes a data structure into a string representation that's unique to ...