Using "FLWOR" expressions in SQL/XML
使用SQL/XML中的 "FLWOR"表达式
FLWOR (" flower ") is often mentioned in the context of XQuery.
FLWOR (“flower”)经常会在XQuery上下文中提到。
You have now seen how to use all the parts of a FLWOR expression except for the let clause.
您已经看到了如何使用FLWOR表达式的所有部分，除了一个部分：let子句。
All FLWOR expressions start with a for or a let expression and end with a return expression.
所有FLOWR表达式都以for或let表达式开始，以return表达式结束。
The same query can be formulated using FLWOR expressions commonly associated with XQuery statements.
可以使用FLWOR 表达式构造同样的查询，这种表达式常常与XQuery 语句相关联。
In many cases, it is possible to write a query by using either a FLWOR expression or a path expression.
在很多情况下，可以任意使用FLWOR表达式或路径表达式编写查询。
The "let" statement is itself composed of a FLWOR (for, let, where, order by, and return) XQuery expression.
“let”语句本身由一个FLWOR（for、let、where、orderby和return）XQuery表达式组成。
FLWOR expressions include at least some of those elements in roughly the order that the acronym suggests.
FLOWR表达式至少包含其中的部分元素，大体上按照缩写词所预示的顺序。
This article focuses on two important kinds of XQuery expressions: FLWOR expressions and path expressions.
本文主要讨论两种重要的XQuery表达式：“FLWOR”表达式和路径表达式。
Although FLWOR expressions are powerful and used in many queries, you can do many things without having to resort to them.
尽管FL WOER表达式功能强大、用途广泛，但不使用它们也可以完成许多任务。
For example, Listing 7 shows how you can move the XPath expression fragment age lt 18 into a where clause in the FLWOR expression.
比如，清单7把XPath表达式片段agelt18放到了FLWOR表达式的where子句中。
Let: you assign values to variable with let, although (as you'll soon see) you won't use let as often as you use the other FLWOR clauses.
let：使用let可以为变量赋值，但是(很快将看到)和其他flwor子句相比，let用的比较少。
Commonly abbreviated to "FLWOR" these expressions may be used for performing joins across multiple XML streams in a similar manner to SQL.
通常缩写为“FLWOR ”的这些表达式可以被用于以类似SQL的方式执行跨多个XML流的连接。
The full-text index finds these XML documents quickly which are then input to the FLWOR expression that extracts all employee names from these documents.
全文本索引迅速找到这些XML文档，随后将它们输入到从这些文档中提取所有员工姓名的FL WOR表达式中。
This clause is used to assign a value (possibly containing a list of several items) to a variable that can be used in other clauses of the FLWOR expression.
该子句用于将一个值(可能包含一个由多项组成的列表)赋给一个变量，这个变量可以在FL WOR表达式的其他子句中使用。
A FLWOR expression is much like a SELECT-FROM-WHERE expression in SQL: it is used to iterate through a list of items and to optionally return something that is computed from each item.
FLWOR表达式非常像SQL中的SELECT - FROM - WHERE表达式——它用于对由多项组成的一个列表进行迭代，并且可以选择返回通过在每一项上进行计算得到的值。
If you are an XPath guru, you will probably find it easier to use a more XPath-oriented approach, whereas those with more SQL experience will probably find the FLWOR syntax more appealing.
如果是XPath高手，那么可能会发现，使用更加面向XPath的方式会更容易一些，而有更多SQL经验的人则会发现FLWOR的语法更有吸引力。
Another misconception about XQuery is that it requires FLWOR (which stands for let, where, order by, return) expressions-similar to the misconception that SQL requires SELECT-FROM-WHERE expressions.
关于XQuery的另一个误解是它需要FLWOR(代表let、where、orderby、return)表达式—类似于SQL需要SELECT - FROM - where表达式这种误解。
Another misconception about XQuery is that it requires FLWOR (which stands for let, where, order by, return) expressions-similar to the misconception that SQL requires SELECT-FROM-WHERE expressions.
关于XQuery的另一个误解是它需要FLWOR(代表let、where、orderby、return)表达式—类似于SQL需要SELECT - FROM - where表达式这种误解。
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