轉換長表數據被廣泛形式SQL或Oracle

Question

我有以下格式 賬戶類

我需要將其轉換爲以下格式在甲骨文

給出的數據集

我怎樣才能做到這一點，因爲它是一個巨大的數據集

Answer 1

您可以使用PIVOT條款。 但是，您需要爲每個帳戶分配它在課程中的列名稱。 您可以使用row_number，rank或dense_rank。

WITH tab AS 
(SELECT 'A1' ACCOUNT, 'C1' CLASS FROM dual UNION ALL 
SELECT 'A2' ACCOUNT, 'C2' CLASS FROM dual UNION ALL 
SELECT 'A3' ACCOUNT, 'C1' CLASS FROM dual UNION ALL 
SELECT 'A4' ACCOUNT, 'C3' CLASS FROM dual UNION ALL 
SELECT 'A5' ACCOUNT, 'C3' CLASS FROM dual UNION ALL 
SELECT 'A6' ACCOUNT, 'C2' CLASS FROM dual UNION ALL 
SELECT 'A7' ACCOUNT, 'C1' CLASS FROM dual UNION ALL 
SELECT 'A8' ACCOUNT, 'C4' CLASS FROM dual UNION ALL 
SELECT 'A9' ACCOUNT, 'C5' CLASS FROM dual UNION ALL 
SELECT 'A10' ACCOUNT, 'C1' CLASS FROM dual UNION ALL 
SELECT 'A11' ACCOUNT, 'C2' CLASS FROM dual UNION ALL 
SELECT 'A12' ACCOUNT, 'C1' CLASS FROM dual UNION ALL 
SELECT 'A13' ACCOUNT, 'C3' CLASS FROM dual UNION ALL 
SELECT 'A14' ACCOUNT, 'C3' CLASS FROM dual UNION ALL 
SELECT 'A15' ACCOUNT, 'C2' CLASS FROM dual UNION ALL 
SELECT 'A16' ACCOUNT, 'C1' CLASS FROM dual UNION ALL 
SELECT 'A17' ACCOUNT, 'C1' CLASS FROM dual) 
SELECT * 
    FROM (SELECT CLASS, 
       ACCOUNT, 
       row_number() OVER (PARTITION BY class ORDER BY account) col_num 
      FROM tab) 
PIVOT (MAX(account) FOR col_num IN (1,2,3,4,5,6,7,8)) 

本示例按字母順序對帳戶進行排序（A1，A10，A12，A16，A3，A7，...）。 如果您需要其他排序，在row_number函數的ORDER BY子句中實現也不難。