81 lines
3.1 KiB
Markdown
81 lines
3.1 KiB
Markdown
# Etl
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We are going to do the `Transform` step of an Extract-Transform-Load.
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### ETL
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Extract-Transform-Load (ETL) is a fancy way of saying, "We have some crufty, legacy data over in this system, and now we need it in this shiny new system over here, so
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we're going to migrate this."
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(Typically, this is followed by, "We're only going to need to run this
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once." That's then typically followed by much forehead slapping and
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moaning about how stupid we could possibly be.)
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### The goal
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We're going to extract some scrabble scores from a legacy system.
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The old system stored a list of letters per score:
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- 1 point: "A", "E", "I", "O", "U", "L", "N", "R", "S", "T",
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- 2 points: "D", "G",
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- 3 points: "B", "C", "M", "P",
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- 4 points: "F", "H", "V", "W", "Y",
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- 5 points: "K",
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- 8 points: "J", "X",
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- 10 points: "Q", "Z",
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The shiny new scrabble system instead stores the score per letter, which
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makes it much faster and easier to calculate the score for a word. It
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also stores the letters in lower-case regardless of the case of the
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input letters:
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- "a" is worth 1 point.
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- "b" is worth 3 points.
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- "c" is worth 3 points.
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- "d" is worth 2 points.
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- Etc.
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Your mission, should you choose to accept it, is to write a program that
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transforms the legacy data format to the shiny new format.
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### Notes
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A final note about scoring, Scrabble is played around the world in a
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variety of languages, each with its own unique scoring table. For
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example, an "A" is scored at 14 in the Basque-language version of the
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game while being scored at 9 in the Latin-language version.
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## Getting Started
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Make sure you have read the [getting started with C++](http://help.exercism.io/getting-started-with-cpp.html)
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page on the [exercism help site](http://help.exercism.io/). This covers
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the basic information on setting up the development environment expected
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by the exercises.
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## Passing the Tests
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Get the first test compiling, linking and passing by following the [three
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rules of test-driven development](http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd).
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Create just enough structure by declaring namespaces, functions, classes,
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etc., to satisfy any compiler errors and get the test to fail. Then write
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just enough code to get the test to pass. Once you've done that,
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uncomment the next test by moving the following line past the next test.
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```C++
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#if defined(EXERCISM_RUN_ALL_TESTS)
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```
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This may result in compile errors as new constructs may be invoked that
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you haven't yet declared or defined. Again, fix the compile errors minimally
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to get a failing test, then change the code minimally to pass the test,
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refactor your implementation for readability and expressiveness and then
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go on to the next test.
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Try to use standard C++11 facilities in preference to writing your own
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low-level algorithms or facilities by hand. [CppReference](http://en.cppreference.com/)
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is a wiki reference to the C++ language and standard library. If you
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are new to C++, but have programmed in C, beware of
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[C traps and pitfalls](http://www.slideshare.net/LegalizeAdulthood/c-traps-and-pitfalls-for-c-programmers).
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## Source
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The Jumpstart Lab team [view source](http://jumpstartlab.com)
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