模块能够选择完全人造的主键——在拒绝所有数据表示角色时分解出唯一性需求的那些主键。
Instead, the modules are able to choose wholly artificial primary keys — ones that isolate the uniqueness requirement while refusing any data-representation role.
可以使用动态关系来关联一组相关业务对象的主键，而使用静态关系来关联非主键属性。
You can use dynamic relationships to correlate primary keys from a set of related business objects and static relationships to correlate non-primary key properties.
如我之前提到的那样，切分迫使您重视主键，因为您将需要亲自管理这些主键。
As I mentioned earlier, sharding forces you to be keenly aware of primary keys, as you'll manage them yourself.
现在已经开始支持自动生成主键和未知的主键字段处理，而且越来越多的人开始使用它。
Primary key generation and unknown primary key field handling is now becoming supported, and more people are beginning to use it.
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.
例如，主键可以是一个唯一的用户ID、一个股票符号，在我们的实例中，主键是一个邮政编码。
For example, the key could be a unique user ID, a stock symbol or, in our case, a zip (postal) code.
因此，如果您依赖于数据库序列(如自动主键生成)，很有可能在一个数据库集中将出现同一个主键。
As a result, if you rely on database sequences (such as for automatic primary key generation), it's likely that an identical primary key will show up across a set of databases.
动态关系通常用于关联一组相关业务对象中的主键，而静态关系通常用于关联一些非主键的属性。
Dynamic relationships are typically used to correlate primary keys from a set of related business objects, whereas static relationships are typically used to correlate non-primary key properties.
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.
但是请注意，我们不能修改您声明的主键列或任何其他的键列；在本例中，EMP _ ID是主键列。
Note, however, that we cannot update the primary key columns or any other key columns that you declare; in this case, EMP_ID is a primary key column.
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.
EJB组件的主键由一个或多个持久性变量组成，对应于数据库中的主键。
The primary key of the EJB component, made up of one or more persisted variables, corresponds to the primary key in the database.
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.
我们还使用由组成ejb主键的值构建的主键类使得把主键指定为一个单独的实体很容易。
We also use a primary key class, constructed from the values comprising the EJB primary key, to make it easy to specify the primary key as a single entity.
可以调整主键的生成策略，甚至指定复合主键。
You can adjust the primary-key creation strategy or even specify a composite primary key.
如果在CREATEtable语句中指定了一个主键，那么主键的首列会被用作分配键。
If a primary key is specified in the CREATE TABLE statement, the first column of the primary key is used as the distribution key.
避免相同主键最安全的方法就是让应用程序(应用程序将管理切分系统)生成主键。
The safest way to prohibit duplicate primary keys is to have your application (which will be managing a sharded system anyway) generate keys.
命令用您定义的唯一主键(在本实例中，唯一主键是邮政编码)来初始化，主键让命令来决定是否调用execute方法。
The command is initialized with whatever you define as your unique key (in this case, a zip code), enabling the command to determine whether to call the execute method.
这用于设置记录的主键，该主键用作针对Doctrine 的一个标记，表明正在处理的记录已经存在于数据库中。
This is used to set the record's primary key and it serves as a signal to Doctrine that the record being processed already exists in the database.
自动生成主键和未知的主键。
Geronimo开发人员目前正在开发的其他功能包括自动为CMP生成主键和未知的主键。
Other features that Geronimo developers are currently working on include automatic primary key and unknown primary key generation for CMP.
您已看到了findByPrimaryKey 子句如何让容器使用EJB组件中的主键作为数据库中行的主键来检索数据库中的行。
You saw how the findByPrimaryKey causes the container to retrieve a row in a database using the primary key of the EJB component as the primary key of the row in the database.
您还可以选择，定义主键值，来在定义表格和添加主键值列本身时使用identity值生成。
Alternatively, you could define the primary key to use Identity value generation at the time you were defining the table and adding the primary key column itself.
如果任一表缺乏一个主键，则cdrstartsec2er命令将创建一个充当主键的er键影子列。
If any of the tables are missing a primary key, the CDR start sec2er command creates an er key shadow column that ACTS the primary key.
而不是依赖你主键字段的命名假设上，或在你的Employee类中的冗余定义(例如，set _ primary_key'X ')，DrySQL从你数据库信息schema中提取雇员表中的主键。
Set_primary_key 'X', DrySQL retrieves the primary key specification for your Employees table from your database's information schema.
表的每一行都是由一个唯一的主键标识的。主键由一列或多列构成。这意味表里不会有重复的行。
Each row of a table is uniquely identified by a primary key composed of one or more columns. This implies that a table may not contain duplicate rows.
可以用主键指定备份集，这个主键可以用LISTBACKUP命令的输入显示出来。
You specify backup sets by primary key, which is shown in the output of the LIST backup command.
主键列由其行选择器中的主键符号标识。
A primary key column is identified by a primary key symbol in its row selector.
主键列由其行选择器中的主键符号标识。
A primary key column is identified by a primary key symbol in its row selector.
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