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How do I check if a column is empty or null in MySQL?
...table which might contain null or empty values. How do I check if a column is empty or null in the rows present in a table?
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Binary Data in JSON String. Something better than Base64
...ch can be represented as one byte according to the JSON spec (if your JSON is transmitted as UTF-8). With that in mind, I think the best you can do space-wise is base85 which represents four bytes as five characters. However, this is only a 7% improvement over base64, it's more expensive to compute,...
What's the difference between session.persist() and session.save() in Hibernate?
Can anyone tell me what's the advantage of persist() vs save() in Hibernate?
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What is the dependency inversion principle and why is it important?
What is the dependency inversion principle and why is it important?
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How is location accuracy measured in Android?
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To answer one part of the question, the number is the radius of 68% confidence, meaning that there is a 68% chance that the true location is within that radius of the measured point in meters. Assuming that errors are normally distributed (which, as the docs say, is not n...
What is a race condition?
...ng multithreaded applications, one of the most common problems experienced is race conditions.
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Should functions return null or an empty object?
What is the best practice when returning data from functions. Is it better to return a Null or an empty object? And why should one do one over the other?
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How and/or why is merging in Git better than in SVN?
I've heard in a few places that one of the main reasons why distributed version control systems shine, is much better merging than in traditional tools like SVN.
Is this actually due to inherent differences in how the two systems work, or do specific DVCS implementations like Git/Mercurial just ha...
Avoid synchronized(this) in Java?
...chronization, some people are very eager to point out that synchronized(this) should be avoided. Instead, they claim, a lock on a private reference is to be preferred.
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C# “as” cast vs classic cast [duplicate]
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With the "classic" method, if the cast fails, an InvalidCastException is thrown. With the as method, it results in null, which can be checked for, and avoid an exception being thrown.
Also, you can only use as with reference types, so if you are typecasting to a value type, you must still use ...