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Skapa ett skalbart databasschema för att lagra golfresultat

Vad var mitt genomsnittliga, högsta och lägsta betyg?

Scenario 1.

select (h1+h2+h3+h4+h5+h6+h7+h8+h9+h10+h11+h13+h14+h15+h16+h17+h18) / 18 as avg_score
      ,greatest(h1,h2,h3,h4,h5,h6,h7,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) as highest
      ,least(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) as lowest
  from scores
 where player_id = 1;

kontra

select avg(score) as avg_score
      ,max(score) as highest
      ,min(score) as lowest
  from scores
 where player_id = 1;

Vilket hål var mitt värsta?

Scenario 2.

select case when h1 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18)  then 'H1'
            when h2 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18)  then 'H2'
            when h3 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18)  then 'H3'
            when h4 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18)  then 'H4'
            when h5 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18)  then 'H5'
            when h6 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18)  then 'H6'
            when h7 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18)  then 'H7'
            when h8 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18)  then 'H8'
            when h9 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18)  then 'H9'
            when h10 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) then 'H10'
            when h11 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) then 'H11'
            when h12 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) then 'H12'
            when h13 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) then 'H13'
            when h14 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) then 'H14'
            when h15 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) then 'H15'
            when h16 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) then 'H16'
            when h17 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) then 'H17'
            when h18 = greatest(h1,h2,h3,h4,h5,h6,h8,h8,h9,h10,h11,h12,h13,h14,h16,h17,h18) then 'H18'
        end as hole_highest_score      
  from scores
 where player_id = 1;

kontra

select hole, score
  from scores s1
 where player_id = 1
   and score = (select max(score)
                  from scores s2
                 where s2.player_id = s1.player_id)

Jag skulle gå med scenario 2 vilken dag som helst :)



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