| Column_name | 数据类型 | 可为空 | 默认值 | 检查 | 键/索引 |
|---|---|---|---|---|---|
| discounttype | varchar(40) | 否 | |||
| stor_id | char(4) | 是 | 外键 stores(stor_id) | ||
| lowqty | smallint | 是 | |||
| highqty | smallint | 是 | |||
| discount | float | 否 |
| discounttype | stor_id | lowqty | highqty | discount |
|---|---|---|---|---|
| Initial Customer | NULL | NULL | NULL | 10.5 |
| Volume Discount | NULL | 100 | 1000 | 6.7 |
| Customer Discount | 8042 | NULL | NULL | 5.0 |