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What is the difference between map and flatMap and a good use case for each?
...ark-shell session:
First, some data - two lines of text:
val rdd = sc.parallelize(Seq("Roses are red", "Violets are blue")) // lines
rdd.collect
res0: Array[String] = Array("Roses are red", "Violets are blue")
Now, map transforms an RDD of length N into another RDD of length N.
For examp...
Difference between OperationCanceledException and TaskCanceledException?
..., as there aren't any actual tasks involved (at least as far as the public API is concerned). See BlockingCollection.TryTake for an example.
I would catch the OperationCanceledException just in case the task is cancelled due to an operation which itself just threw OperationCanceledException - you p...
Can you create nested WITH clauses for Common Table Expressions?
...
Essentially the post means, that you can't do it, but it is not a big problem.
– peterh - Reinstate Monica
May 30 '17 at 14:40
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SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?
... cross join produces a cartesian product between the two tables, returning all possible combinations of all rows. It has no on clause because you're just joining everything to everything.
A full outer join is a combination of a left outer and right outer join. It returns all rows in both tables t...
What is a stored procedure?
... a couple of ways. Most major DBMs support stored procedures; however, not all do. You will need to verify with your particular DBMS help documentation for specifics. As I am most familiar with SQL Server I will use that as my samples.
To create a stored procedure the syntax is fairly simple:
CRE...
What is App.config in C#.NET? How to use it?
... connection string is hard coded in my coding, there is no problem for installing it in my system, but for other systems there is.
...
What is Ember RunLoop and how does it work?
...machty.s3.amazonaws.com/ember-run-loop-visual/index.html
Update 5/9/2013: all the basic concepts below are still up to date, but as of this commit, the Ember Run Loop implementation has been split off into a separate library called backburner.js, with some very minor API differences.
First off, re...
Map implementation with duplicate keys
...ons-collections and Guava have several implementations for that. Multimaps allow for multiple keys by maintaining a collection of values per key, i.e. you can put a single object into the map, but you retrieve a collection.
If you can use Java 5, I would prefer Guava's Multimap as it is generics-aw...
Image Get Requests with AngularJS
... practice to use Interpolation with ngStyle. Reference: docs.angularjs.org/api/ng/directive/ngStyle
– Abdul Rauf
Jul 18 '17 at 7:23
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How to run a python script from IDLE interactive shell?
...s.call(['python', 'helloworld.py']) # Just run the program
subprocess.check_output(['python', 'helloworld.py']) # Also gets you the stdout
With arguments:
subprocess.call(['python', 'helloworld.py', 'arg'])
Read the docs for details :-)
Tested with this basic helloworld.py:
import sys
if le...