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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...y.
Side effects are propagated to replicas too.
correction: both REPLACE and INSERT...ON DUPLICATE KEY UPDATE are non-standard, proprietary inventions specific to MySQL. ANSI SQL 2003 defines a MERGE statement that can solve the same need (and more), but MySQL does not support the MERGE statemen...
Asking the user for input until they give a valid response
...put the input method in a while loop. Use continue when you get bad input, and break out of the loop when you're satisfied.
When Your Input Might Raise an Exception
Use try and except to detect when the user enters data that can't be parsed.
while True:
try:
# Note: Python 2.x users s...
Simulator or Emulator? What is the difference?
While I understand what simulation and emulation mean in general, I almost always get confused about them. Assume that I create a piece of software that mimics existing hardware/software, what should I call it? A simulator or an emulator?
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What is the difference between save and export in Docker?
I am playing around with Docker for a couple of days and I already made some images (which was really fun!). Now I want to persist my work and came to the save and export commands, but I don't fully understand them.
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Good reasons NOT to use a relational database?
Can you please point to alternative data storage tools and give good reasons to use them instead of good-old relational databases? In my opinion, most applications rarely use the full power of SQL--it would be interesting to see how to build an SQL-free application.
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What is the difference between Ruby 1.8 and Ruby 1.9
...m not clear on the differences between the "current" version of Ruby (1.8) and the "new" version (1.9). Is there an "easy" or a "simple" explanation of the differences and why it is so different?
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How much does it cost to develop an iPhone application? [closed]
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I'm one of the developers for Twitterrific and to be honest, I can't tell you how many hours have gone into the product. I can tell you everyone who upvoted the estimate of 160 hours for development and 40 hours for design is fricken' high. (I'd use another phrase, bu...
Android Studio installation on Windows 7 fails, no JDK found
I downloaded Android Studio and attempted to launch the program.
29 Answers
29
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git undo all uncommitted or unsaved changes
...rying to undo all changes since my last commit. I tried git reset --hard and git reset --hard HEAD after viewing this post . I responds with head is now at 18c3773... but when I look at my local source all the files are still there. What am I missing?
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Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
...always be the name of the executable? Or is this just a common convention and not guaranteed to be true 100% of the time?
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