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SQL - HAVING vs. WHERE
...nce HAVING works correctly.
As a rule of thumb, use WHERE before GROUP BY and HAVING after GROUP BY. It is a rather primitive rule, but it is useful in more than 90% of the cases.
While you're at it, you may want to re-write your query using ANSI version of the join:
SELECT L.LectID, Fname, Lnam...
C++, What does the colon after a constructor mean? [duplicate]
...e the body of the constructor executes.
For case #1, I assume you understand inheritance (if that's not the case, let me know in the comments). So you are simply calling the constructor of your base class.
For case #2, the question may be asked: "Why not just initialise it in the body of the cons...
Why do I need 'b' to encode a string with Base64?
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base64 encoding takes 8-bit binary byte data and encodes it uses only the characters A-Z, a-z, 0-9, +, /* so it can be transmitted over channels that do not preserve all 8-bits of data, such as email.
Hence, it wants a string of 8-bit bytes. You create those in Python ...
How to find files that match a wildcard string in Java?
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Try FileUtils from Apache commons-io (listFiles and iterateFiles methods):
File dir = new File(".");
FileFilter fileFilter = new WildcardFileFilter("sample*.java");
File[] files = dir.listFiles(fileFilter);
for (int i = 0; i < files.length; i++) {
System.out.println...
What's the role of adapters in Android?
I want to know when , where and how adapters are used in the context of Android.
10 Answers
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Check if a number is int or float
... isinstance(False, (int, float)) = True), I needed not isinstance(n, bool) and isinstance(n, (int, float)) instead
– YTZ
Jun 7 at 16:53
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How do I sort a list of dictionaries by a value of the dictionary?
I have a list of dictionaries and want each item to be sorted by a specific property values.
18 Answers
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Why does C# not provide the C++ style 'friend' keyword? [closed]
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Having friends in programming is more-or-less considered "dirty" and easy to abuse. It breaks the relationships between classes and undermines some fundamental attributes of an OO language.
That being said, it is a nice feature and I've used it plenty of times myself in C++; and would lik...
console.writeline and System.out.println
What exactly is the technical difference between console.writeline and System.out.println ?
I know that System.out.println writes to standard output but is this not the same thing as the console?
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Repairing Postgresql after upgrading to OSX 10.7 Lion
...ked when trying to connect to the psql server. When I do it from the command line using
15 Answers
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