89 lines
2.4 KiB
Markdown
89 lines
2.4 KiB
Markdown
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# 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 transform the legacy data
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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 "E" is scored at 2 in the Māori-language version of the
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game while being scored at 4 in the Hawaiian-language version.
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## Running tests
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Execute the tests with:
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```bash
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$ elixir etl_test.exs
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```
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### Pending tests
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In the test suites, all but the first test have been skipped.
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Once you get a test passing, you can unskip the next one by
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commenting out the relevant `@tag :pending` with a `#` symbol.
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For example:
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```elixir
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# @tag :pending
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test "shouting" do
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assert Bob.hey("WATCH OUT!") == "Whoa, chill out!"
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end
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```
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Or, you can enable all the tests by commenting out the
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`ExUnit.configure` line in the test suite.
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```elixir
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# ExUnit.configure exclude: :pending, trace: true
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```
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For more detailed information about the Elixir track, please
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see the [help page](http://exercism.io/languages/elixir).
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## Source
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The Jumpstart Lab team [http://jumpstartlab.com](http://jumpstartlab.com)
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## Submitting Incomplete Solutions
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It's possible to submit an incomplete solution so you can see how others have completed the exercise.
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