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Simultaneously merge multiple data.frames in a list
I have a list of many data.frames that I want to merge. The issue here is that each data.frame differs in terms of the number of rows and columns, but they all share the key variables (which I've called "var1" and "var2" in the code below). If the data.frames were identical in terms of columns, ...
MVC (Laravel) where to add logic
Let's say whenever I do a CRUD operation or modify a relationship in a specific way I also want to do something else. E.g., whenever someone publishes a post I also want to save something to a table for analytics. Maybe not the best example but in general there's a lot of this "grouped" functionalit...
How do I create and access the global variables in Groovy?
I need to store a value in a variable in one method and then I need to use that value from that variable in another method or closure. How can I share this value?
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What specific productivity gains do Vim/Emacs provide over GUI text editors?
This isn't meant as a troll or flamebait or anything like that. I've been using Vim as my console-editor of choice for a couple months now (for editing configuration files while in my terminal), but I don't think I could stand it for my normal, every day work of writing web applications, which I ...
How can I specify a branch/tag when adding a Git submodule?
How does git submodule add -b work?
12 Answers
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How do you create a random string that's suitable for a session ID in PostgreSQL?
I'd like to make a random string for use in session verification using PostgreSQL. I know I can get a random number with SELECT random() , so I tried SELECT md5(random()) , but that doesn't work. How can I do this?
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Run an untrusted C program in a sandbox in Linux that prevents it from opening files, forking, etc.?
I was wondering if there exists a way to run an untrusted C program under a sandbox in Linux. Something that would prevent the program from opening files, or network connections, or forking, exec, etc?
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How to check if one of the following items is in a list?
I'm trying to find a short way to see if any of the following items is in a list, but my first attempt does not work. Besides writing a function to accomplish this, is the any short way to check if one of multiple items is in a list.
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What are the best practices for using a GUID as a primary key, specifically regarding performance?
I have an application that uses GUID as the Primary Key in almost all tables and I have read that there are issues about performance when using GUID as Primary Key. Honestly, I haven't seen any problem, but I'm about to start a new application and I still want to use the GUIDs as the Primary Keys, b...
How do I check if a string is a number (float)?
What is the best possible way to check if a string can be represented as a number in Python?
33 Answers
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