嗨,我是想顯示所有飲料各製造商除了碳酸一個人的使用產生存在和子查詢,但它給了我一個空集,請幫我出如何使用子查詢存在?
mysql> 'select * from drink';
+----------------+------------+----------------+
| name | type | manf |
+----------------+------------+----------------+
| Coca-cola zero | carbonated | Coca-Cola |
| Mirinda | carbonated | PepsiCo |
| Big Apple | carbonated | Murree Brewery |
| Big Lemon | carbonated | Murree Brewery |
| Big Orange | carbonated | Murree Brewery |
| Peach Malt | malt | Murree Brewery |
| Lemon Malt | malt | Murree Brewery |
| Apple Malt | malt | Murree Brewery |
| New Coke | carbonated | Coca-Cola |
| Diet Coke | carbonated | Coca-Cola |
| Pepsi | carbonated | PepsiCo |
| Fruita vitals | Juice | Nestle |
| Twister | Juice | Shezan |
| Nescafe | cofee | Nestle |
| Cappuccino | Cofee | Gloria Jeans |
| Caffe Latte | Cofee | Gloria Jeans |
| Flat White | Cofee | Gloria Jeans |
+----------------+------------+----------------+
17 rows in set (0.00 sec)
查詢我試過,但它不是給我結果
SELECT * FROM drink WHERE NOT EXISTS (SELECT * FROM drink WHERE drink.type = 'carbonated');
你確定你解釋正確的問題? EXISTS將用於「顯示除了那些製造碳酸飲料的製造商以外的所有飲料」 – Barmar