LEI为自动生成和外键表的填充提供了一个功能。
LEI provides a function for the automatic generation and population of the external key table.
这些键值可以存储在现有的数据表中或者存储在单独创建的称作外键表的表中。
These keys can be stored in an existing data table or in a separately created table referred to as the external key table.
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。
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.
创建一个外键，以便将这个新表与已有的雇员表相连接。
Create a foreign key to link this new table with the existing employee table.
一列使用一个外键链接到表单上(表中的一行)。
One column links to the form (the row in the table) using a foreign key.
例如，日期表的外键对于一个文档的每个关键词不会重复。
For example, the foreign key to the date table is not repeated for every keyword of a document.
当将数据分解成多个具有外键关系的表时，这尤其重要。
This is important when data is decomposed into multiple tables having foreign key relationship.
以这种方式控制ETL工作，对于保证按适当次序装载包含主键或外键依赖的数据仓库表十分有用。
Controlling the ETL work in this manner can be useful for guaranteeing the proper sequence for loading data warehouse tables that contain primary or foreign key dependencies.
它们由逻辑数据模型转换而来，其中实体和关系转换为表、列、主键、外键以及约束。
They are transformations of logical data model where the entities and relationships are transformed into tables, columns, primary keys, foreign keys, and constraints.
了解关系数据库、数据模型、惟一键、主键、外键和表联结。
Learn about relational databases, data models, unique keys, primary keys, foreign keys, and table joins.
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。
Early enterprise applications used database tables and foreign-key relationships between them to model entities.
事实表可以根据一或多个外键过滤。
The fact tables can be filtered on one or more of their foreign keys.
星型模式要求生成并适当使用事实表和维表的主键或外键。
The star schemas require the generation and proper use of primary or foreign keys for the fact and dimension tables.
表中的外键维护着组间以及组内表之间的管理。
Foreign keys within tables maintain the relationship between intra-group and inter-group tables.
因此，如果源表在RI关系中为父表或子表，您需要捕捉外键定义并在移动表之后重新创建它们。
Therefore, if your source table was either a parent or child in an RI relationship, you need to capture the foreign keys definition and recreate them after the table is moved.
如果是，则从维表中读取已有的ID，并用它作为事实表中新条目的外键。
If so, the existing ID is read from the dimension table and used as the foreign key for the new entries in the fact table.
否则，从序列获取一个新的键值，用它作为维表中新条目的主键和事实表中的外键。
Otherwise, a new key value is taken from the sequence and used for both, a new entry in the dimension table and as a foreign key in the fact table.
维度表需要作为主键数据的通用键；这将作为事实表的外键。
A dimension table needs a generalized key as the primary key data; this becomes the foreign key in the fact table.
您还可以在次表中建立外键，以链接主表中的主键。
You can also establish a foreign key in a secondary table to link with a primary key in a primary table.
联合表：(可选)将子类映射到与父类映射到的表具有外键关系的表。
Joined table: (Optional) the child class is mapped to a table that has a foreign key relationship to the table to which the parent is mapped.
索引下推使用下推键执行事实表外键索引的查询。
An index pushdown USES the pushed-down keys to perform index lookups on a foreign key index of the fact table.
我们的虚拟外键基于TB_RIGHT表的两个列。
Our virtual foreign key is based on two columns from the TB_RIGHT table.
例如，如果存在依赖表(例如表中有一个外键，该外键引用数据要被装载到的目标表)，那么这些表可能被设为CHECK PENDING状态。
For example, if there are any dependent tables (tables that have a foreign key referencing the table into which data is to be loaded, for example), they might be placed in the CHECK PENDING state.
在包中显示事实表的外键。
确保参照完整性(referential integrity,ri)关系中的依赖表拥有与外键匹配的索引。
Ensure dependent tables in a referential integrity (ri) relationship have indexes that exactly match the foreign key.
给 Transformer建模师提供事实表中发现的外键。
Expose foreign keys found in fact tables to Transformer modelers.
SQLObject允许将表之间的关系定义为外键。
SQLObject lets you define relationships among tables as foreign keys.
假设您添加了一个新的状态码waituntiltomorrow，并将它应用到todo_foreign表(包含外键的表1)中的某一项。
Let's say you add a new status code, waituntiltomorrow, and apply it to one item in the todo_foreign table (table 1, with the foreign keys).
运行rakedb:migrate以创建SUBSCRIPTIONS表并将外键列添加到SUBJECTS 中。
Run rake db:migrate to create the SUBSCRIPTIONS table and add foreign key columns to SUBJECTS.
通过在将fact表中的外键与dimension 表中的主键进行连接时采用like数据类型（例如 INT32 to INT32），可提高查询性能。
Query performance can be improved by leveraging like data types (i.e. INT32 to INT32) when joining foreign keys in a fact table to primary keys in a dimension table.
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