数据库宝石迷阵-这个解决方案是如何工作的?

我对珠宝游戏带来的编程挑战感兴趣。这似乎是一个简单的游戏,但从程序上讲,它看起来更复杂。

在我寻找如何评估董事会的提示时,我遇到了 this QUIZ 在简单的谈话中由好人装腔作势。他们已经公布了获胜的答案,但如果我真的能摸索出解决方案是如何工作的,我会被涂上焦油和羽毛。我可以看到,它与矩阵和将单元格值与其行和列分组有关,但这是目前为止我所了解的。有人能帮我把它再细分一点吗?

已发布的解决方案(测验的详细信息在上面的链接中):

--====== Table matches needs to be loaded only once
CREATE TABLE matches(offsetRow1 INT, offsetCol1 INT, offsetRow2 INT, ofsetCol2 INT, directions VARCHAR(20))
-- for horizontal 
INSERT INTO matches VALUES(-1, -1, -1, -2, 'up')
INSERT INTO matches VALUES(-1, -1, -1, 1, 'up')
INSERT INTO matches VALUES(-1, 1, -1, 2, 'up')        
INSERT INTO matches VALUES( 1, -1, 1, -2, 'down')           
INSERT INTO matches VALUES( 1, -1, 1, 1, 'down')
INSERT INTO matches VALUES( 1, 1, 1, 2, 'down')       
INSERT INTO matches VALUES( 0, -2, 0, -3, 'left')     
INSERT INTO matches VALUES( 0, 2, 0, 3, 'right')            
-- for verical
INSERT INTO matches VALUES(-2, -1, -1, -1, 'left')
INSERT INTO matches VALUES(-1, -1, 1, -1, 'left')
INSERT INTO matches VALUES( 1, -1, 2, -1, 'left')
INSERT INTO matches VALUES(-2, 1, -1, 1, 'right')
INSERT INTO matches VALUES(-1, 1, 1, 1, 'right')
INSERT INTO matches VALUES( 1, 1, 2, 1, 'right')
INSERT INTO matches VALUES(-2, 0, -3, 0, 'up')
INSERT INTO matches VALUES( 2, 0, 3, 0, 'down')

--==================================================
;WITH CTE
      AS
  (
  SELECT
        [Row] = CAST( [#] AS INT ),
        [Col] = CAST( [Col] AS INT ),
        [Value]
    FROM bejeweled
        UNPIVOT ([Value] FOR [Col] IN ([1],[2],[3],[4],[5],[6],[7],[8],[9])) unpvt
  )
SELECT DISTINCT T.Row, T.Col, T.Value, directions
  FROM CTE T
      JOIN CTE T1
      ON T.Value = T1.Value
      JOIN CTE T2
      ON T.Value = T2.Value
      JOIN matches
      ON (T1.Row - T.Row) = offsetRow1
    AND (T1.Col - T.Col) = offsetCol1
    AND (T2.Row - T.Row) = offsetRow2
    AND (T2.Col - T.Col) = ofsetCol2
  ORDER BY T.Row, T.Col