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must appear in the GROUP BY clause or be used in an aggregate function
...erver just don't allow this at all. Mysql used to allow it by default, but now since 5.7 the administrator needs to enable this option (ONLY_FULL_GROUP_BY) manually in the server configuration for this feature to be supported...
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When should I use a struct instead of a class?
... was overly eager. return false is what should have been there, correcting now.
– Andrei Rînea
Nov 13 '14 at 15:11
An...
Practical uses for AtomicInteger
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The test are quite old now (more than 6 years) it might me interesting to retest with a recent JRE. I didn't went deep enough in the AtomicInteger to answer but as this is a very specific task it'll use synchronization techniques that are only work...
SQL SELECT speed int vs varchar
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@RobertMunteanu Hey Robert, apologies I know this is an old post but can I kindly check...on the following: in order to query integers, i have to link each string column to another table (relationship). however, that means more joining operations are required for ea...
Hidden Features of Java
...d it, never heard of it before.
ThreadLocals are typically not so widely known as a way to store per-thread state.
Since JDK 1.5 Java has had extremely well implemented and robust concurrency tools beyond just locks, they live in java.util.concurrent and a specifically interesting example is the j...
How to replace a set of tokens in a Java String?
... is only available starting with Java 1.5 (which should be pretty standard nowadays, but you never know). Instead of that you might also use Java's class MessageFormat for replacing the placeholders.
It supports placeholders in the form '{number}', so your message would look like "Hello {0} Please ...
Responsive image map
... thank you Tom, we were having a discussion on a question on CodeReview, now I wish I could remember the question....
– Malachi
Apr 8 '14 at 14:01
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What is the difference between task and thread?
...vide a rudimentary example of threads working to complete a task? I don't know if the threads are doing work that are independant between each others or do they do some teamwork calculation?
– pensum
Feb 18 at 2:04
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How does the String class override the + operator?
...erence value is then converted to type String by string
conversion.
Now only reference values need to be considered:
If the reference is null, it is converted to the string "null" (four ASCII characters n, u, l, l).
Otherwise, the conversion is performed as if by an invocation of...
How to permanently add a private key with ssh-add on Ubuntu? [closed]
... a specific key and if it doesn't find it, then it adds it with ssh-add.
Now the first time I open my terminal I'm asked for the passwords for my private keys and I'm not asked again until I reboot(or logout - I haven't checked) my computer.
Since I have a bunch of keys I store the output of ssh-...