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CROSS JOIN vs INNER JOIN in SQL
... @iliketocode "old syntax for joins" is not clear, you'd better talk about SQL-89 and SQL-92 standards
– Ivanzinho
Jul 25 '18 at 13:50
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Pass a data.frame column name to a function
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Hi @Luis, check out this answer
– EcologyTom
Apr 1 '19 at 10:13
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Simple explanation of MapReduce?
...case, the function to "double every number" is function x = x * 2. And without mappings, I could write a simple loop, say
A = [1, 2, 3]
foreach (item in A) A[item] = A[item] * 2
and I'd have A = [2, 4, 6] but instead of writing loops, if I have a map function I could write
A = [1, 2, 3].Map(x =&...
Using HTML5/Canvas/JavaScript to take in-browser screenshots
...owser window to create a screenshot that is submitted with your feedback about a bug.
5 Answers
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Explain how finding cycle start node in cycle linked list work?
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This is Floyd's algorithm for cycle detection. You are asking about the second phase of the algorithm -- once you've found a node that's part of a cycle, how does one find the start of the cycle?
In the first part of Floyd's algorithm, the hare moves two steps for every step of the torto...
Why does Ruby have both private and protected methods?
...d had to do whether a subclass could inherit a method, but it's actually about where the method can be called from. Thanks!
– Kyle Slattery
Aug 20 '10 at 20:49
3
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What is the difference between a reference type and value type in c#?
... copies so there are two redundant values in memory.
As classes are missed out.it losses all the oop benifits
Reference type:
Holds a memory address of a value not value
Example:
Class
Storage:
Stored on heap
Advantages:
When you pass a reference variable to a method and it changes it ind...
Encrypting & Decrypting a String in C# [duplicate]
...e".
The RijndaelManaged class does indeed normally require you to "muck about" with byte arrays, salts, keys, initialization vectors etc. but this is precisely the kind of detail that can be somewhat abstracted away within your "wrapper" class.
The following class is one I wrote a while ago to per...
Should I compile release builds with debug info as “full” or “pdb-only”?
...ch could severely hamper your ability to track down the problem.
A note about performance:
Both John Robbins and Eric Lippert have written blog posts about the /debug flag, and they both indicate that this setting has zero performance impact. There is a separate /optimize flag which dictates whet...
Foreign key constraints: When to use ON UPDATE and ON DELETE
...//dev.mysql.com/doc/refman/5.6/en/stored-program-restrictions.html#stored-routines-trigger-restrictions
==> See below the last edit, things are moving on this domain
Triggers are not activated by foreign key actions.
And I do not think this will get fixed one day. Foreign key constraints ...