| 1. | Corrected the description of entity integrity
更正了实体完整性的说明。 |
| 2. | Entity integrity defines a row as a unique entity for a particular table
实体完整性将行定义为特定表的唯一实体。 |
| 3. | Is a constraint that enforces entity integrity for a specified column through a unique index
一个约束，该约束通过唯一索引来强制指定列的实体完整性。 |
| 4. | Is a constraint that provides entity integrity for a specified column or columns by using a unique index
通过唯一索引为指定的一列或多列提供实体完整性的约束。 |
| 5. | Is a constraint that enforces entity integrity for a specified column or columns by using a unique index
通过唯一索引对指定的一列或多列强制实体完整性的约束。 |
| 6. | This column , or columns , is called the primary key of the table and enforces the entity integrity of the table
这样的一列或多列称为表的主键( pk ) ，用于强制表的实体完整性。 |
| 7. | Unique is a constraint that provides entity integrity for a specified column or columns through a unique index
一个约束，该约束通过唯一索引为一个或多个指定列提供实体完整性。 |
| 8. | A virtual table that presents data in a specific order , by highlighting certain items , or by showing only certain items
表中每一行的唯一值。主键可以针对一个或多个列而存在。这称为实体完整性。 |
| 9. | Entity integrity enforces the integrity of the identifier columns or the primary key of a table , through unique indexes , unique constraints or primary key constraints
实体完整性通过unique索引、 unique约束或primary key约束，强制表的标识符列或主键的完整性。 |
| 10. | Entity integrity constraints , referential integrity constraints , and user - defined most intergrity constraints of relational database were all preserved after the conversion
转换过程可保留关系数据库的实体完整性约束、参照完整性约束和绝大部分的用户自定义完整性约束。 |
