如果要更改与主键表中的列相关的列，可修改关系的外键侧。
Modify the foreign key side of a relationship if you want to change which columns are related to columns in the primary key table.
主键表的一个记录，关联到关联表中，存在，没有，或者有一个，或者多个记录。这是最重要的也是最常见的关系。
The primary key table contains only one record that relates to none, one, or many records in the related table. This is the most commonly used type of relationship.
在关系模型中主键是特殊的事物：它对于表的每个记录(行)必须是唯一的。
A primary key is a special thing in the relational model: It must be unique to each record (row) of a table.
而且这种方法在为每个表的主键提供完全一致和可预测的名称以及格式方面有着额外的优势。
And the approach has the additional advantage of giving every table's primary key an identical and predictable name and format.
如果表的主键或惟一性约束中指定了这个列，那么不允许使用这个子句(SQLSTATE 42831)。
This clause is not allowed if the column is specified in the primary key, or in a unique constraint of the table (SQLSTATE 42831).
注意：企业复制要求在所有表上定义主键。
Note: Enterprise replication requires that primary keys be defined on all tables.
该数据集还描述了这两个表的主键。
The DataSet also depicts the primary keys of the two tables.
表间关系、主键列和其他有关目标数据的信息也是通过元数据对象指定的。
Inter-table relationships, primary key columns, and other information about the target data is specified through the metadata object as well.
主复制要求所有节点通过访问主节点来获得关于表、列和主键的字典信息。
Master replicates require all nodes to access the master node to obtain the dictionary information about tables, columns, and primary keys.
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。
For foreign key creation, another table with a primary key with a compatible data type is required.
其原因是：规范化需要更多的表，连接等操作，主键、索引，从而需要更多的内部操作。
The reason: Normalization requires more tables, table joins, keys and indexes and thus more internal database operations for implement queries.
除了具有主键以外，表通常还有一些辅键。
As well as having primary keys, tables typically have some secondary keys.
数据库为一个表格的主键生成值(通过扩展，为相关表生成外主键)，从而将程序从这项任务的重担中解放出来。
Having the database generate values for the primary key for a table (and by extension, any foreign key values for related tables) eliminates the burden from the application from having to do so.
简单地运行两次会产生错误，因为相同的星星名称（作为表的主键）使用了两次，则会由于重复的主键值导致错误。
Simply running it twice will produce an error, because the same star names (which are the primary key for the table) are used again, causing an error with duplicate primary key values.
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.
它们包含了持有者的专有名称的信息，可以作为路由表的主键。
They contain information in the subject's distinguished name, which can be used as a key into a routing table.
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.
模板使用关于数据库的模式信息、一组表、列和主键定义一组主副本和一个副本集。
A template USES schema information about a database, a group of tables, columns, and primary keys to define a group of master replicates and a replicate set.
如果任一表缺乏主键，那么该表将被改变，以添加充当主键的ER影子列键。
If any of the tables are missing primary keys, those tables are altered to add er shadow column keys that act as primary keys.
复制模板包含数据库的架构信息、一组表、列属性、标识行的主键。
Replication templates contain schema information about a database, a group of tables, column attributes, and the primary keys that identify rows.
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.
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。
The latter is actually a primary key lookup against the parent table and constitutes the foreign key constraint verification.
表的主键和所有惟一索引都必须是相关分区键的超集。
The primary key and any unique index of the table must be a superset of the associated partitioning key.
一个参数是描述数据库的关联数组集合：表名、列名、主键和外键。
One parameter is a collection of associative arrays that describe the database: table names, column names, primary keys, and foreign keys.
辅键与其它表中的主键对应。
The secondary keys correspond with primary keys in other tables.
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.
如果在模板的实行中服务器上没有这些表和主键，则根据模板定义创建表和主键。
If the tables and primary keys do not exist on the server during the realization of the template, then the tables and primary keys are created according to the template definitions.
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.
原因是DB2UDBSAMPLE数据库中的其他表没有主键，因此没有索引信息可以关联惟一的ECO 键。
The reason for this is that the other tables in the DB2 UDB SAMPLE database have no primary key, and hence no index information to associate a unique ECO key with.
首先，您通常要具有一个映射到对应数据库表主键的(代理)对象标识符。
First, you usually want to have a (surrogate) object identifier that maps to the primary key of the corresponding database table.
应用推荐