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UNIQUE-constraints是什么意思_翻译中文_怎么读

UNIQUE-constraints

网络释义:唯一约束;唯一性约束;唯一性限制

网络释义

1.唯一约束唯一约束unique constraints):要求表中在指定的列上没有两行具有相同的值。主键约束( primary key constraints):要求 …

2.唯一性约束唯一性约束unique constraints)可以确保表中的各行,对于值为非NULL的给定列或者列组都具有唯一值。如同于外键约束, …

3.唯一性限制唯一性限制(Unique Constraints ) 检查限制(Check Constraints ) 预设值限制(Default Constraints ) 栏位的可否NULL限制(Nullabil…

4.唯一性的限制唯一性的限制Unique Constraints)是让我们强制某个栏位 中所含的值一定不能有重复的资料,(可以用来设定候选键(candi…

例句释义:,唯一约束,唯一性约束,唯一性限制

1.Automatically created indexes Adaptive Server Anywhere automatically creates indexes for primary keys and for unique constraints.自动创建的索引AdaptiveServerAnywhere自动创建主键和唯一约束的索引。

2.In addition, the CREATE TABLE and ALTER TABLE statements can be used to set locking granularity on PRIMARY KEY and UNIQUE constraints.另外,CREATETABLE和ALTERTABLE语句还可用于设置PRIMARYKEY和UNIQUE约束的锁定粒度。

3.The abipty to create primary and foreign keys as well as CHECK and UNIQUE constraints on columns of this type.能够对此类型的列创建主键和外键以及CHECK和UNIQUE约束。

4.You can attach multiple unique constraints to a table, whereas you can attach only one primary key constraint to a table.可将多个唯一约束附加到表,但是只能将一个主键约束附加到表。

5.This dialog box contains a set of properties for constraints (except unique constraints) attached to the tables in your database.此对话框包含附加到数据库表的约束(唯一约束除外)的一组属性。

6.Design entity keys. Considerations include FOREIGN KEY constraints, PRIMARY KEY constraints, and UNIQUE constraints.设计实体键。考虑外键约束,主键约束和唯一性约束条件。

7.UNIQUE constraints ensure that no duppcate values are entered and that an index is created to enhance performance.UNIQUE约束可确保不输入重复的值,并确保创建索引来增强性能。

8.Searches for duppcates of new index key values in insert and update operations, to enforce PRIMARY KEY and UNIQUE constraints.搜索与插入和更新操作中的新索引键值重复的值,以强制PRIMARYKEY和UNIQUE约束。

9.The DROP INDEX statement does not apply to indexes created by defining PRIMARY KEY or UNIQUE constraints.DROPINDEX语句不适用于通过定义PRIMARYKEY或UNIQUE约束创建的索引。这些约束是分别使用。

10.A one-to-one relationship is created if both of the related columns are primary keys or have unique constraints.当两个相关列都是主键或都具有唯一约束时,将创建一对一关系。