null value

If this column is not sorted, a null value is returned, and the@ formulas in the agent will not continue executing.

如果该列未进行排序，将返回空值，代理中的@formulas将不再继续执行。

It's the situation where, for instance, someone passes a null value to a method not coded to handle nulls.

比方说，把null值传入一个并未编写如何处理null值的方法中，这就是一种边界情况。

Null value is not allowed in unique index or primary key.

唯一性索引或主键中不允许有空值。

Decompositions for Relational Schema Under Null Value Circumstances Into BCNF With Lossless Joins

空值环境下关系模式到（N）BCNF无损连接分解

Fuzzy database is a database which can handle fuzzy information, which provides a way for handling null value.

模糊数据库是指能够处理模糊信息的数据库，它为空值的处理提供了一条重要的途径。

Hold conditions of data dependencies under the null value circumstances

空值环境下的数据依赖保持条件

If the corresponding class, field, or method is not generic, a null value is passed when calling the method.

若相应的类、字段或方法非泛型，则在调用方法时将返回null值。

But, in DB2 z/ OS if a UNIQUE index is created on a column, then only one NULL value can be inserted into it.

但是在DB2z/OS中，如果在列上创建UNIQUE索引，那么只能在其中插入一个NULL值。

When you want to determine whether a given row includes a comment, you no longer need to check for a null value in the COMMENT column.

确定某一个行是否包含注释时，不再需要检查COMMENT列的null值。

Disposal of Redundancy in the Relational Model Under the Fuzzy Null Value Environment

模糊空值环境下关系模型的冗余处理

A general, good practice is not to allow null ( that is, no value) columns in a relational database, because when you attempt to read such a column, you get a null value exception.

通常，一种优秀的实践就是不要在关系数据库中使用null（即没有值）列，因为当您试图读取这类列时，您将得到一个null值异常。

Completeness of Axiom System of Functional Dependencies Under Null Value Circumstances

空值环境下函数依赖公理系统的完备性

Using 5 Valued Logic Under Complete Semantics of Null Value

空值完全语义下五值逻辑的使用

Failure. The NULL value has been passed as a parameter.

失败. 将空指针NULL传给了一个参数.

Null value is introduced to the extended relational model of paper [ 1].

本文在〔1〕扩展关系模型中引入属性级的不完全信息空值。

Normal Form Theory of Relational Database under Fuzzy Null Value Circumstances

模糊空值环境下关系数据库的范式理论