For simplicity, we chose not to validate entries into the list by returning a value of null each time the validator is run.
为简单起见，我们选择不验证列表中的条目，每次运行检验器时返回空值。
We may not know what type t represents, but we know that the null literal is a valid value for any reference type.
我们可能不知道t类型代表什么，但我们知道null字母对任何引用类型而言是一个空值。
It is important that you use a null modem cable; if you use a typical serial cable, the target computer expects a serial device and not another serial port, and you cannot debug the computer.
有一点很重要，那就是要使用零调制解调器电缆，如果您使用普通的串行电缆，目标计算机则期望与串行设备通信，而不是与另一个串行端口通信，这样您就无法调试该计算机。
Several wiring layouts are in use, because the null modem connection is not covered by a standard.
有多种连接方式可供选择，因为标准中并未涵盖零调制解调器连接。
Initially, this routine checks if the passed inquiry context is not NULL and is for a group member inquiry.
这个例程首先检查传递的查询上下文是否非null，以及是否是用于组成员查询的上下文。
If the input binding parameter is not NULL, then it means that the endpoint resides on a remote host.
如果输入绑定参数不是NULL，就意味着端点在远程主机上。
If a default value is not specified, the variable is initialized to NULL.
如果没有指定默认值，则初始变量为NULL。
If the URI does not exist in the internal hash table, a null is returned.
如果内部哈希表中没有URI，将返回空值。
For example, if a before trigger supplies value to a NOT NULL column, then the before trigger is executed first and a value is supplied to the column so that the NOT NULL constraint isn't violated.
例如，如果一个BEFORE触发器给一个NOT null列提供值，那么先执行BEFORE触发器，给列提供值，所以不会违反NOT NULL约束。
A cheque is null and void if any one of the particulars mentioned in the preceding paragraph is not specified thereon.
支票上未记载前款规定事项之一的，支票无效。
Elements in positions 11 and up do not exist (note that this is not the same as being NULL). Therefore, a statement such as.
位置11以及更高位置中的元素都不存在(请注意这不同于NULL)。
But as we hope we've shown in the table, that really represents an array with a single element whose value is null, not a null array.
但是，正如我们希望的，在表中已经显示，它真正表示的是含有单一元素的数组，元素的值为“零”(null)，而不是一个“零”(null)数组。
If the HTTP method is GET (currently not used by JSF forms), the form data has already been appended to the URL and send is called with a null parameter.
如果HTTP方法是GET(当前未被JSF表单使用)，那么表单数据应该已经追加到此url，并会用null参数调用send 。
These are generally implicit design decisions in the APIs such as where a value can be null, or where a numeric value is not expected to be negative.
在API的设计中，有一些决策是不言而喻的，比如何时值可以为null，或者何时数字值不能为负。
For example, data classified as "unknown" usually indicates a column that is null or empty and probably not used.
例如，类别为“未知”的数据通常表明一个列只有null值或者为空，可能不被使用。
If the value of the transportTModelKey parameter is not null, then a transport categorization keyedReference is added; its value is the value of the transportTModelKey parameter.
如果transportTModelKey参数的值不为空，就添加一个传输类别 keyedReference ；它的值即是 transportTModelKey 参数的值。
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。
The single quotation mark in front of the null list is used to tell Scheme that you are using as data and not as a part of your parse tree.
空列表前面的单引号用来告诉scheme您正在使用作为数据，而不是用它作为解析树的一部分。
Because null is not a valid default value for an annotation, I provide some basic defaults that can be easily tested for, so I can identify the value that was specified.
由于null不是标注的有效默认值，因此这里提供了一些便于测试的基本默认值，以便识别被指定的值。
Notice in Listing 9 that the instance does have a valid (meaning it is not null) toAddress value.
注意在清单9 中，该实例确实有一个有效（意为非 nul ）的toAddress值。
SQL USES a small integer which contains a zero if the column is not null or -1 if the column contains nulls.
如果列不包含空值，则SQL使用一个包含一个0的小整数；反之则包含- 1。
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。
In the context of the NorthWind Customer Manager; when a Customer ID that does not exist in the system is used to load a Customer detail, then a Null instance should be returned.
在Northwind客户管理的上下文中，当使用系统中不存在的客户ID加载客户细节时，应该返回一个空实例。
In Oracle 10g, if there is a BEFORE INSERT TRIGGER and a NOT NULL constraint on a table, then the BEFORE TRIGGER is executed first, and then the constraint check is performed.
在Oracle10g中，如果表上同时存在BEFORE INSERT触发器和NOT NULL约束，那么先执行BEFORE触发器，然后执行约束检查。
If this value is set to null or empty string, CLP throws a JCC exception: Column not updatable.
如果将这个值设置为null或空字符串，clp会抛出JCC异常：Column not updatable。
This is because you have not yet defined the Customer in a schema, which caused the boFacory.create method to return a null.
这是因为您尚未在模式中定义Customer，这将导致 boFacory.create方法返回 null。
In this example, if the Map on line 1 does not contain the person named "Bob," a null pointer exception will result on line 5 when the person is asked for his name.
在这个例子中，如果第1行的Map不包括一个名为“bob”的人，那么在第5行询问person的名字时就会出现null指针异常。
For example, if you are creating a Customer table and the CustomerID is marked as not null, then when you define the primary key, CustomerID will show as a candidate column.
例如，如果您要创建一个Customer表并且CustomerID 被标记为not null，则当您定义主键时，CustomerID将会显示为备选列。
A workaround to this is to supply a default value to the not NULL column whose value comes from a BEFORE INSERT TRIGGER, so that the constraint is not violated.
一种解决方法是给从BEFORE INSERT触发器取得值的NOT null列提供默认值，这样就不会违反约束。
When a unique index is created on a column in Oracle 10g, it ensures that the NOT NULL values entered in that column are unique.
当在Oracle10g中的列上创建UNIQUE索引时，会确保此列中输入的NOT null值是惟一的。
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