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NULL values inside NOT IN clause
...t I thought were identical queries one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the con...
What is Linux’s native GUI API?
Both Windows (Win32 API) and OS X (Cocoa) have their own APIs to handle windows, events and other OS stuff. I have never really got a clear answer as to what Linux’s equivalent is?
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Schrödingers MySQL table: exists, yet it does not
...er_table, check the data directory to make sure you have both an .frm file and .ibd file for the table in question. If it's MYISAM, there should be a .frm, .MYI and a .MYD file.
The problem can usually be resolved by deleting the orphaned file manually.
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Different types of thread-safe Sets in Java
There seems to be a lot of different implementations and ways to generate thread-safe Sets in Java.
Some examples include
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What is the difference between an int and a long in C++?
... (an answer by example) with some of the details below regarding the C++ standard. The draft for C++0x is at open-std.org/JTC1/SC22/WG21/docs/papers/2008/n2798.pdf and it is marked up so you can see the differences between it and the last rev.
– Patrick Johnmeyer
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What is the difference between HTML tags and ?
...uld like to ask for some simple examples showing the uses of <div> and <span> . I've seen them both used to mark a section of a page with an id or class , but I'm interested in knowing if there are times when one is preferred over the other.
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How do I animate constraint changes?
I'm updating an old app with an AdBannerView and when there is no ad, it slides off screen. When there is an ad it slides on the screen. Basic stuff.
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Difference between encoding and encryption
What is the difference between encoding and encryption?
10 Answers
10
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How to create SBT project with IntelliJ Idea?
I just got started with Scala/LiftWeb/Sbt developing, and I'd like to import a Sbt project in IntelliJ Idea.
Actually, I managed to import my project in two different ways:
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Pros and cons to use Celery vs. RQ [closed]
...ect that requires implement some background jobs (mostly for email sending and heavily database updates). I use Redis for task broker. So in this point I have two candidates: Celery and RQ . I had some experience with these job queues, but I want to ask you guys to share you experience of using t...