Victor Kean vickean
vickean
/ sqlite3_cheat_sheet.txt
Created
April 12, 2016 06:17
— forked from youjingwong/gist:18a4ca28ee632efa631a
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| #1. Count the votes for Sen. Olympia Snowe, whose id is 524. | |
| SELECT COUNT(*) FROM votes WHERE politician_id = 524 ; | |
| #2. Now do that query with a JOIN statement without hard-coding the id 524 explicitly, querying both the votes and congress_members table. | |
| SELECT COUNT(*) FROM congress_members INNER JOIN votes ON congress_members.id = votes.politician_id WHERE congress_members.name = "Sen. Olympia Snowe" ; | |
| #3. How about Rep. Erik Paulsen? How many votes did he get? | |
| SELECT COUNT(*) FROM congress_members INNER JOIN votes ON congress_members.id = votes.politician_id WHERE congress_members.name = "Rep. Erik Paulsen" ; | |
| #4. Make a list of Congress members that got the most votes, in descending order. Exclude the create_at and updated_at columns. |
vickean
/ elegant_sudoku_solver.rb
Last active
June 9, 2016 18:47
— forked from pstachula-dev/gist:7419321
Sudoku
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| require 'Benchmark' | |
| class Sudoku | |
| attr_accessor :puzzle | |
| def initialize | |
| @puzzle = '' | |
| @game = Array.new(9) | |
| @game.map! { Array.new(9) } | |
| 9.times do |i| |