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How do I compare strings in Java?
I've been using the == operator in my program to compare all my strings so far.
However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.
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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, ...
Can I use GDB to debug a running process?
Under linux, can I use GDB to debug a process that is currently running?
8 Answers
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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 do I copy a hash in Ruby?
I'll admit that I'm a bit of a ruby newbie (writing rake scripts, now). In most languages, copy constructors are easy to find. Half an hour of searching didn't find it in ruby. I want to create a copy of the hash so that I can modify it without affecting the original instance.
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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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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...
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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Merge and interleave two arrays in Ruby
I have the following code:
11 Answers
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