The <many-to-many> tag's column attribute specifies the foreign key column in the link table that relates the link table to the mapping table for the target class.
<many-to-many>标签中的column属性用来指定连接表与目标类的映射表链接的外键。
If informational check constraints exist on the primary key column, you should explicitly specify informational check constraints on their corresponding foreign key columns. For example.
如果在主键列上存在信息检查约束,那么应该在它们相应的外键列上指定信息检查约束。
Listing 5 adds a trail and a location to the database, managed with a foreign key pointing from the location_id column in trails to the id column in locations.
清单5向数据库添加了一条赛道和一个地点,由从trails中的location_id列指向locations中的id列的外键管理。
In addition to the id primary key, you've declared the customer_id column to be a foreign key referencing the customer table.
除了id主键以外,还声明了customer_id列作为引用客户表的外键。
For the sake of simplicity, consider VARCHAR as the default type for every column that is not a primary or a foreign key.
为了简单起见,考虑把VARCHAR作为除主键和外键外的所有列的默认类型。
The name attribute defines the foreign key on the table to which the Customer class is mapped, and the referenced column defines the primary key to which the table CustomerOrder is mapped.
名称属性在customer类映射到的表上定义外键,参考列定义Table CustomerOrder映射到的主键。
Index push-downs require only a single-column index on the fact table, although they can use a multi-column index if the required foreign-key column is the first key in the index.
索引下推只需要事实表的单列索引,虽然在所需的外键列是索引的第一个键的情况下可以使用多列索引。
The column attribute specifies the column in the mapping table for the owning class that is used as the foreign key to the target class.
colum n属性指定当前类的映射表与目标类用作外键的列。
The column pdb_id is the foreign key that links atom coordinates to the corresponding PDBML document in the PDBXML table.
列pdb_id是一个外键,链接了原子坐标与pdbxml表中对应的PDBML文档。
Since dayTrader-plan.xml did not use the foreign-key-column-on-source element in this relationship, the foreign key should be on the OrderEJB.
因为在此关系中dayTrader-plan.xml没有使用foreign-key-column-on-source元素,所以外键应该在 OrderEJB 上。
If you don't include a foreign column in the declaration, Derby assumes that you're referencing the primary key of the other table.
如果在声明中不包括外键,Derby将假定引用的是其他表的主键。
You'd need to create a new table and also add a new column representing the foreign key to each article to point to a blog.
需要创建一个新表,还要添加指向blog的每个文章的外键。
Remember that when foreign-key-column-on-source is not used, you will need to find the reverse mapping yourself.
请记住,当foreign - key - column - on - source没有使用时,您需要自己寻找逆向映射。
Shows how to perform table-row filtering using Boolean, foreign-key, and enumeration column types.
演示如何使用布尔值、外键和枚举列类型来执行表行筛选。
Shows how to perform table-row filtering using Boolean, foreign-key, and enumeration column types.
演示如何使用布尔值、外键和枚举列类型来执行表行筛选。
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