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                # DBMS 中的多值依賴 > 原文: [https://beginnersbook.com/2015/04/multivalued-dependency-in-dbms/](https://beginnersbook.com/2015/04/multivalued-dependency-in-dbms/) 當表中存在多個**獨立**多值屬性時,會發生多值依賴。 **例如**:考慮一家自行車制造公司,每年在每個車型中生產兩種顏色(黑色和白色)。 | `bike_model` | `manuf_year` | `color` | | --- | --- | --- | | M1001 | 2007 | Black | | M1001 | 2007 | Red | | M2012 | 2008 | Black | | M2012 | 2008 | Red | | M2222 | 2009 | Black | | M2222 | 2009 | Red | 這里的列`manuf_year`和顏色彼此獨立并依賴于`bike_model`。在這種情況下,這兩列可以說是多值的,取決于`bike_model`。這些依賴關系可以表示如下: ``` bike_model ->> manuf_year bike_model ->> color ```
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