SQL CASE 語句

May 9, 2017

如何在 SQL 選擇語句中使用 CASE 語句來處理 if-then-else 邏輯。

INSERT INTO table_new(newColumnA, newColumnB, newColumnC, newColumnD)
SELECT columnA AS newColumnA,
       columnB AS newColumnB,
       CASE columnC
           WHEN 'value1' THEN 'newValue1'
           WHEN 'value2' THEN 'newValue2'
           ELSE 'newDefaultValue'
       END AS newColumnC,
       columnD AS newColumnD
FROM table_old

See reference for more.

sql