null

null

美 [nʌl] 　英 [nʌl]

• adj.没有价值的；无用的；【法】无法律效力的；【科技】没有
• n.【数】数字零；【计】空位；空白符号；【电子】无信号
• v.抵消；〈罕〉【法】宣布无效；〈罕〉彻底消灭
• 网络空值；空字符；空指针

词形变化

反义词

同义词

英汉双解

习惯用语

英汉解释

英英解释

例句

This tip addresses one of those cases: the distinction between an array which is null, and an array which has no elements.

这里介绍的技巧用于处理其中的一个情况：一个为“零”的数组和一个没有元素的数组之间的差别。

NULL constants cannot be inserted into a timestamp column through a distributed query.

无法通过分布式查询将NULL常量插入timestamp列中。

This certificate shall be considered null and void in case of any alteration.

任何修改，本证书将被视为无效。

In todo_foreign, that would require two columns; the deletion date might be null to indicate that the item is still active.

在todo_foreign中，这将需要两个列；删除日期可能为null，表示该事项仍然在活动中。

For a calculation of the exact benefits of NULL and system default compression, it would be necessary to count these values per column.

若要精确计算NULL压缩和系统默认值压缩所节省的空间，则需要逐列地计算这些值的数量。

In China, where the deprivation of a minor violation of the law and unable to work the right to inherit part of the heirs, null and void.

在中国，凡违背法律规定剥夺未成年人和无劳动能力的继承人的继承权的部分，归于无效。

To declare a variable and initialize it without assigning it a particular value, assign it the JScript value null.

若要在不分配特定值的情况下声明一个变量并对其进行初始化，请为其分配JScript值null。

The results do not make it easy to distinguish a NULL in the data from a NULL that represents a failure to join.

从结果中很难区分数据中的NULL值和表示联接失败的NULL值。

Attribute value with a null reference assigned to a reference type or to a nullable value type.

属性值等同于分配给引用类型或分配给可为空值类型的空引用。

The constructor function has no parameters and returns an instance of the type with all of its attributes set to null values.

构造函数没有参数，并且返回的类型实例中的所有属性都为空。

Experimenters have yet to see such a frame, but the null result may simply be for want of sufficient precision.

实验学家目前还没看到这样的座标，不过看不出迹象并不代表没有，也许只是缺乏足够的精确度使然。

Columns of a unique index are allowed to be NULL, while columns in a unique constraint are not.

唯一索引的列可以为NULL，而唯一约束的列不能为NULL。

It used to be that the goal in econometric work was to get results that were statistically significant, to reject the null hypothesis.

过去，搞经济计量学时，目标往往是争取让获得的结果，在统计上有显著意义，这样就能拒绝零假设。

Consequently, any information on the investigation that comes from another source is null and void if it has not been validated by the BEA.

因此，从其他来源的任何调查的信息是无效的，如果它没有被验证了BEA。

This routine initially checks if the passed inquiry context is not NULL and if it a context for group member.

它首先检查传递的查询上下文是否非NULL，以及是否是组成员的上下文。

For this reason, a scene which has no formal links always has at least one link in it, though this link has a ref value of "null" .

因此，没有正式链接的场面也要包含至少一个链接，这个链接的ref值是“null”。

Remember, in C, a string is nothing but an array of characters with a terminating NULL character (ASCII 0).

请记住，在C语言中，字符串只是一个带有终止NULL字符（ASCII0）的字符数组。

The goal with validation is to avoid some simple errors, such as trying to put a NULL into a field that doesn't accept them.

验证的目标就是要避免一些简单错误，例如尝试将NULL放入不接受这种值的字段。

Though you did not specify that column, the Rails migration created it for you anyway, with auto_increment and NOT NULL.

虽然没有指定这个列，但是Rails迁移会自动创建它，并具有auto_increment和NOTNULL属性。

A value of NULL is not considered to be greater than, less than, or equivalent to any other value, including another value of NULL.

NULL值不视为大于、小于或等于任何其他值，包括另一个NULL值。

The zero or null matrix denoted by 0 is definde as a matrix all of whose elements are zero.

如果一个矩阵的所有元素都为零，则称它为零矩阵。

Exclude columns: The name of the columns that you want to be excluded can be null.

排除列：您希望被排除的列名称可以为空。

At least one of the null values must be a typed NULL.

至少应有一个空值为NULL类型。

The property acquired as a result of a contract shall be returned after the contract is confirmed to be null and void or has been revoked.

合同无效或者被撤销后，因该合同取得的财产，应当予以返还。

The SUM function returns the total sum of a column in a given selection. NULL values are not included in the calculation.

使用SUM函数可以返回给定的选择中列的所有记录值的累计合。NULL值不包括在内。

The argument that is set to null could have been used to transmit additional properties to the dynamic page instance.

设置为null的参数可用于将附加属性传送到动态页面实例。

The following table illustrates the relationship between the existence of a default and the definition of a column as NULL or NOT NULL.

下表说明默认值的存在与将列定义为NULL或NOTNULL之间的关系。

When you work with strings with a null value, the result of the concatenation depends on the session settings.

处理具有空值的字符串时，串联结果取决于会话设置。

The following example adds a column that allows null values and has no values provided through a DEFAULT definition.

以下示例将添加一个允许空值的列，而且没有通过DEFAULT定义提供的值。

Since the requirement is to only suppress nulls, the visual null suppression can be replaced by the Null suppression on the actual query.

因为需求是仅抑制nulls，可视的nullsuppression可由实际查询上的Nullsuppression替换。

If you were using an Object-based stack, you would simply return null, but a generic stack could be used with value types as well.

如果您使用基于Object的堆栈，则可以简单地返回null，但是您还可以通过值类型来使用一般堆栈。

When null, the data point takes up no space just as if the column didn't exist.

当值为null时，数据指针就完全不占用空间，就像这个列不存在一样。

We have examined the occurrence of GSTM1 null, one of the glutathione S-transferase mu genes, in a control and a Parkinson's disease group.

我们审核了发生GSTM1空白，其中谷胱甘肽S-转移酶基因亩，在控制和治疗帕金森病组。

In a Java environment, if an object is null, trying to manipulate it causes an error.

在一个Java环境中，如果一个对象为空，试图操作它将导致错误。

If it slackened while expanding, its strength would be absolutely null, and it would be even less likely to survive.

如果它在扩张中松懈下来，它的实力绝对无效，它更加难以存活。

If the applicant has no insurable interest to the subject matter of insurance, the insurance contract will be null and void.

保险利益决定保险合同的效力问题，投保人对保险标的不具有保险利益的，保险合同无效。

If the value is NULL , the subscription has no scheduled time falling within the specified time range .

如果该值为NULL，则表示订阅的计划时间不在指定的时间范围内。

The bindtextdomain() function returns the directory pathname currently bound to the domain. If it fails, null pointer will be returned.

函数返回当前绑定到域的目录路径名。如果失败，返回空指针。

The null value in the system is an empty object that has no value.

系统中的null值是一个没有值的空对象。

The error is caused by the fact that there is an overhead of two bytes for varying length and a one-byte overhead for null.

造成这个错误的原因是，变化的长度占用2字节，null占用1字节。

DT_SONAME This element holds the string table offset of a null-terminated string, giving the name of the shared object.

SONAME类型的数组项保存着一个以NULL结尾的字符串在字符串表中的偏移量，这个字符串是共享object的名字。