Understanding these foreign-key definitions is key to understanding the mapping of EJB relationships.
理解这些外键的定义是理解ejb关系映射的关键。
Early enterprise applications used database tables and foreign-key relationships between them to model entities.
早期的企业应用程序使用数据库表和表之间的外键关系进行实体建模。
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。
Fortunately, with a basic understanding of the primary key and foreign key strategy employed, you can find anything you want.
幸运的是,随着对使用的主键和外键策略的基本理解,可以找到您所需的全部内容。
Create a foreign key to link this new table with the existing employee table.
创建一个外键,以便将这个新表与已有的雇员表相连接。
For foreign key creation, another table with a primary key with a compatible data type is required.
对于创建外键,则需要另外一个具有主键的表,且该主键具有兼容的数据类型。
One column links to the form (the row in the table) using a foreign key.
一列使用一个外键链接到表单上(表中的一行)。
Minimize the triggers, CHECK and foreign key constraints, and generated columns for the table.
尽量减少表上的触发器、检查和外键约束以及生成的列。
When we are able to relate without ambiguity any association end to a foreign key, we can apply the correspondence to specify to which primary key the foreign key refers.
当我们能够清楚无二义地联系任何关联结尾和外键时,我们可以把通讯应用于指明外键指向的是哪个主键。
All tables which have foreign key relationships to the selected table — and all foreign key tables from the selected table — will be visualized in the diagram illustrated in Figure 7, following.
对所选择的表具有外键关系的所有表——以及来自所选表的所有外键表——将会在下面的图7中被可视化的显示出来。
This category of overhead includes CHECK constraint verification and foreign key constraint (referential integrity (ri)) verification.
这一类的开销包括检查约束验证和外键约束(参照完整性(RI))验证。
This is important when data is decomposed into multiple tables having foreign key relationship.
当将数据分解成多个具有外键关系的表时,这尤其重要。
During the foreign key enforcement, the server USES the sequential scan, instead of foreign key index.
在外键加强过程中,服务器使用顺序扫描,而不是外键索引。
Also, notice how the primary key and foreign key properties represent the relationships on the Deals on Wheels class diagram.
此外,注意主键和外来键属性是怎样表达车辆调度类图的关系的。
Similarly if two tables are connected via a foreign key, they are connected.
与此类似,如果两张表通过一个外键连接起来,我们也称其为连接的。
Missing join predicates, but only if a foreign key is defined.
丢失连接谓词,只在定义了外键的情况下。
For example, the foreign key to the date table is not repeated for every keyword of a document.
例如,日期表的外键对于一个文档的每个关键词不会重复。
After the foreign key constraint with index disabled is dropped and recreated, the reversion completes successfully.
终止和重新创建索引禁用的外键之后,降级就成功完成了。
The foreign key has not only an identifier to identify a record, but also a type to identify the table.
外键不仅具有标识记录的标识符,而且还具有标识表的一个类型。
New syntax for disabling an index for foreign key constraint was added to use with the ALTER statement.
用于为外键约束禁用索引的新语句被使用alter语句添加来使用。
Indexes are defined on all primary and foreign key columns to support efficient joins between the 12 tables.
全部主键和外键均定义了索引,来支持12个表之间有效的结合。
Figure 4 depicts the referential integrity (foreign key relationship) shown by a UML association between the tables.
图4描述了由一个表之间的UML关联所表示的引用完整性(外键关系)。
This makes it virtually impossible for us to create a foreign key.
这使得我们几乎不可能创建外键。
Details from the Foreign Key Analysis allow the user to understand the overlap of actual values and quickly isolate discrepancies.
外键分析得出的详细信息使用户可以理解实际值的重叠,并快速消除差异。
All DOC_IDs are unique to meet the foreign key constraints.
所有DOC_ID都是惟一的,以满足外键约束。
The latter is actually a primary key lookup against the parent table and constitutes the foreign key constraint verification.
索引扫描实际上是对父表进行主键查找,并完成外键约束验证。
It is similar to a foreign key in a relational database.
它类似于关系数据库中的外键。
You don't need to worry about messing around with the primary key or foreign key.
您无需担心处理主键或外键的麻烦。
Each one-to-one association is buried as a foreign key in the table of either class.
每个一对一的关联在表中任一类中充当外键。
Our virtual foreign key is based on two columns from the TB_RIGHT table.
我们的虚拟外键基于TB_RIGHT表的两个列。
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