Rails will use a JOIN SQL statement or a strategy in which multiple queries are performed.
Rails将使用一个JOIN sql语句或一个执行多个查询的策略。
Listing 9 contains the same three-way join SQL statement that was used in Listing 1 to introduce the concept of access paths and query execution.
清单9包含相同的三路联接sql语句，其用在清单1上以介绍访问路径和查询执行的概念。
Table functions are powerful because it can make any data source appear like a DB2 table, which can be then used in normal SQL queries, join operations, grouping, and so on.
表函数的功能很强大，因为它可以使任何数据源看起来类似于db2表，然后就可以用于常规的SQL查询、连接操作和分组等。
Remember that this matches each CD with each artist, producing the equivalent with a SQL join.
记住，这样将匹配每张 CD和每位艺术家，从而得到相当于SQL 连接的效果。
In this regard, the query is similar to a left outer join in SQL.
从这种意义上说，查询与 SQL中的左外连接相似。
Each data source is then read by a simple SQL SELECT statement, and the join is completed within the InfoSphere DataStage process.
只通过简单的SQLselect语句对每个数据源进行读取，并且在InfoSphereDataStage流程之内完成连接。
For example, using SQL to create a multi-table outer join that outputs its results to a new XML document is much more complicated to the average developer than writing XQuery.
比方说，对于一般开发人员，使用SQL创建输出结果为新xml文档的多表外连接查询要比编写XQuery复杂得多。
The parts of Person that are stored in Employee aren't "sliced off," as can happen in a regular SQL query that fails to join every derived subclass table in a table-per-class model.
存储在Employee中的Person的各部分不会被“切掉”，而当定期SQL查询未能成功地将派生子类表加入到table - per - class模型中时，这种被“切掉”的现象就会发生。
The optimization of SQL queries utilize sophisticated features, such as: query rewrite, multiple join methods, detailed statistics, parallelism etc.
SQL查询的优化利用了一些复杂的功能，例如：查询重写、多连接(join)方法、详细的统计、并行性等。
This means you can get all the benefits of typical SQL join queries without the burden of predefining their relationships in the database layer.
这意味着您能够获得典型的SQL联合查询的所有好处，但又不需要在数据库层预定义它们的关系。
As part of the transformation, the optimizer also determines the correct table join order, rewrites expressions, and eliminates any redundancy from the SQL.
作为转换的一部分，优化器还决定正确的表联接顺序，重写表达式，并从SQL中消除任何冗余。
In SQL terms, this merge calls for an outer join, which matches each row in the work items data set to the single row in the states data set with a matching state ID.
在sql术语中，该合并会调用一个外层联系，它会将工作项数据集合中的每一行，与状态数据集合中的单个行使用匹配状态ID来匹配起来。
The SQL JOIN statement has long been in the toolkit of database programmers, allowing you to combine the data contained in two or more relational database tables based upon a common attribute.
数据库编程人员对SQL JOIN语句的使用由来已久，通过该语句可以基于相同的属性将两个或更多关系数据库表中的数据组合到一起。
The information needed can be obtained by using the SQL JOIN operator.
需要能够通过使用SQL JOIN操作符来获得这些信息。
Building an SQL JOIN command starts as a regular SQL SELECT command, but instead of specifying fields from just one table, you can specify fields from more than one table.
构建SQL JOIN命令时，开始仍是常规的SQLSELECT命令，但这里不是仅指定来自一个表的字段，而是指定来自多个表的字段。
This is especially helpful for long SQL statements that include JOIN operations or complex WHERE clauses that might wrap over several lines.
对于包含JOIN操作或复杂的where子句的sql长语句(可能包含几行语句)，这一点特别有用。
SQL expressions will need to be created from these attributes to form the join predicates of the SQL statement.
需要从这些属性创建SQL表达式，从而形成sql语句的联结谓词。
A JOIN in SQL is simply a way of saying that a field in one table must correspond to another field in a different table.
SQL中的JOIN只是简单说明一个表中的字段必须对应于另一个表中的另一字段的方法。
The attributes on this side will need to be converted to SQL expressions to form the join predicates of the SQL statement.
这一边上的属性需要转换为SQL表达式，从而形成sql语句的联结谓词。
One big advantage of a native XML database is that it can run queries that combine (or join, in SQL parlance) information contained in multiple XML documents.
原生XML数据库一个很大的优点是，可以运行能够将包含在多个 XML 文档中的信息组合在一起的查询（或者按SQL 的说法称为联结）。
You can then use an SQL inner join to get the frequency with which each company in the list is mentioned, as in Listing 10.
然后您可以使用一个SQLinnerjoin语句来得到列表中每个公司被提到的频率，如清单10所示。
Similarly, you can represent any specific join you might perform (as in the SQL examples in Listing 3 and Listing 4) in XML equally easily.
您也可以同样轻松地以XML表示可能执行的任何特定联接(如清单3和清单4中的SQL示例所示)。
Using a correlated join, the NEW_OL_LOCAL SQL Table Function processes each item in the list separately.
通过使用一个关联连接(correlated join)，NEW_OL_LOCALsql表函数逐个处理列表中的每种产品。
To ensure the desired SQL Join Syntax is used, turn on the option in the project Governors dialog.
要确保采用了所需的SQL连接语法，可启用projectGovernors对话框中的选项。
Finally, I discussed the different possible SQL JOIN commands and provided examples of where and when you can use them.
最后，我谈论了可能出现的不同的SQL JOIN命令，并提供了一些例子，解释应该在何时何处使用这些 SQL JION 命令。
For this, you need to extend your SQL SELECT command using a JOIN.
为此，您需要使用一个JOIN来扩展SQLSELECT命令。
Hibernate will then automatically perform the SQL JOIN to retrieve all the necessary information from both tables, as shown in Listing 6.
Hibernate会自动执行SQL的JOIN，从两个表中检索所有必要信息，如清单6所示。
You could also write the SQL Command to explicitly mention the INNER part of the join.
您也可以编写SQL命令显式地提到JION的INNER部分。
In order to speed up the query evaluation, we established the structured mapping for the XML data stored in RDB, and therefore, the frequency of join operations in SQL statement can be decreased.
为了加快查询的执行，我们对存放在关系库中的XML数据建立结构化映射，以减少SQL语句中连接操作的数目。
In order to speed up the query evaluation, we established the structured mapping for the XML data stored in RDB, and therefore, the frequency of join operations in SQL statement can be decreased.
为了加快查询的执行，我们对存放在关系库中的XML数据建立结构化映射，以减少SQL语句中连接操作的数目。
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