處理刪除和更新通過比較兩個表

Question

我有兩個表，我想在這種意義上比較，如果circuitId是相同的兩列它應該檢查如果CHECKSUM列是否相同，如果他們是同樣也不會在表格中插入新記錄。如果circiutId不在表中，它應該添加一個新行。

到目前爲止，我有這個，但我不知道如何實現，以便在WHEN MATCHED THEN的邏輯裏面。所以它內部檢查校驗和是否相同，從而插入記錄？

MERGE INTO ARCHIVE.F1_CIRCUITS n 
     USING EXTRACT.F1_CIRCUITS o 
     ON 
     (n.CIRCUITID= o."circuitId") 
     WHEN MATCHED THEN 
     WHEN NOT MATCHED THEN 
      INSERT VALUES 
      ("circuitId","circuitRef","name","location","country","lat","lng","alt","url", CURRENT_TIMESTAMP, NULL, HASH_MD5("circuitId","circuitRef","name","location","country","lat","lng","alt","url"), 'C', 0) 

Answer 1

我覺得insert是足夠了：

INSERT INTO ARCHIVE.F1_CIRCUITS (. . .) 
    SELECT . . . 
    FROM EXTRACT.F1_CIRCUITS o 
    WHERE NOT EXISTS (SELECT 1 
         FROM ARCHIVE.F1_CIRCUITS n 
         WHERE o.circuitid = n.circuitid AND 
          o.checksum = n.checksum 
        ); 

的. . .是不同的列名和表達式。