Question

我有这个SQL查询，它执行GROUP BY将所有包含相同Player_id但不包含相同Game_id的行合并在一起：

SELECT p.Player_id, 
       p.Name, 
       p.Position, 
       SUM(s.Goals) AS goalsb, 
       SUM(s.Assists) AS assistsb, 
       SUM(s.Points) AS pointsb
FROM Dim_Player AS p 
INNER JOIN Fact_Statistics AS s ON s.Player_id = p.Player_id
GROUP BY p.Player_id, p.Name, p.Position
ORDER BY pointsb DESC, goalsb DESC

我想要做的是每次GROUP BY将一行与另一行合并时，植入一个COUNT来创建一个名为“Games playing”的新列。例如：

Player_id      Game_id    goalsb
8470598        465        1
8470598        435        1

这将与上面的SQL查询组合在一起成为：

Player_id          goalsb
8470598            2

但我想要这个：

Player_id          goalsb       Games_played
8470598            2            2

Answer 1

如果您重复Game_id并且想要计算不同的值，则可以添加

COUNT (DISTINCT Game_id)

子句到你的SELECT陈述。

Answer 2

向选择查询添加计数功能。 COUNT（*）计算组中的每一行，与所选列无关。

SELECT p.Player_id, p.Name, p.Position, SUM(s.Goals) AS goalsb, SUM(s.Assists) AS assistsb, SUM(s.Points) AS pointsb, COUNT(*) as [Games_played] 
FROM Dim_Player AS p INNER JOIN Fact_Statistics AS s ON s.Player_id = p.Player_id
GROUP BY p.Player_id, p.Name, p.Position, s.Game_id
ORDER BY pointsb DESC, goalsb DESC

如何计算T-SQL中的GROUP BY行

2 个答案: