Step 7: Adding a Table Join operator.
步骤7:添加一个Table join操作符。
Once again, the second query requires no table join.
第二查询也不需要表连接。
This gives us 23 tables and a 24-table join to retrieve a DICOMData object.
这会产生23个表,而且检索一个DICOMData对象要连接 24 个表。
But in simple terms, a table join creates a composite table from two other tables.
但是用简单的术语来说,一个表格联系会从两个不同的表格创建一个组合表格。
Here you have a three-table join involving a UNION, and from the db2exfmt output pertaining to the query, you have.
假设有一个涉及UNION的三表连接和来自查询的db 2 exfmt输出。
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。
Specify the condition for the table Join operator by connecting the tables using the unique term number, which is SKILL_ID in the result set of the text analysis and TERM_ID in the taxonomy table.
通过使用唯一的术语编号将表连接起来,为Table Join操作符指定条件,术语编号为文本分析结果集中的SKILL_ID,和位于分类表中的TERM_ID。
Before the join begins, the database server first applies filters if there are any, and then sorts the rows for each table on the join column.
连接开始之前,如果有筛选器,那么数据库服务器首先会应用它们,然后对连接列上每个表中的行进行分类。
A star join query typically involves a fact table and several dimension tables, with join predicates between the fact table and each dimension table.
一个星型连接查询通常包含一个事实表和几个维度表,事实表和每个维度表之间都有连接谓词。
This is a lot faster than a nested loop join of two table scans without any index usage.
这比不使用任何索引的两个表扫描的嵌套循环连接要快得多。
Customize the formatting ordering of the predicates according to various criteria such as local predicates or join predicates, and table references.
根据各种标准,如本地谓词或连接谓词,以及表引用来定制谓词的格式化顺序。
The join table allows you to persist books with a single author as well as books with multiple authors.
连接表允许将具有一个作者的图书和具有多个作者的图书持久化。
This query plan uses hash join for each join between the fact table and a dimension table.
这个查询对每个事实表和维度表之间的连接使用散列连接。
If specified, it can only take the value 'TRUE' to indicate that the given table must be the first table accessed in a join query.
如果指定了的话,它将只接受“TRUE”值,表示给定表必须是连接查询中进行访问的第一个表。
In the query access plan shown in Listing 9, notice a join between the table EMPLOYEE and a table function, GENROW.
在清单9所示的查询访问计划中,要注意表employee和一个表函数GENROW间的一个连接。
Predicates are reordered and regrouped based on the kind of predicate (local or join) and the table reference.
重新排序和重新组合谓词是基于谓词的种类(本地或联接)和表引用。
The join is performed by scanning the inner table of the hash join, CUSTOMERS, and generating a lookup table by hashing the join column values.
该连接的执行过程包括扫描散列连接中的内表CUSTOMERS,并通过散列连接列的值生成一个查找表。
To get the remaining information, join this table with table E2KNVVM007.
为了获得剩余的信息,将此表与表e2KNVVM 007联接在一起。
The performance improvement depends on the selectivity of the filter on the dimension table from which the join keys are pushed down.
性能的提高取决于连接键被下推时所在维度表的过滤选择度。
Creating a join table to manage this relationship would be the right thing to do.
创建一个连接表来管理这个关系会非常适合。
You would probably need to set up a many-to-many relationship with a join table, requiring several joins to determine the actors for a particular movie.
您可能需要使用一个联接表设置一个多对多关系,这需要几个联接来确定某个电影的演员。
This provides the table a default order and a fast way to join the table against other tables.
这为表提供一个默认顺序和快速方式来联接其他表。
The larger the probe table is in a hash join, the slower the join is.
散列连接中的探测表越大,连接就越慢。
For table CUST_ORDER_HEADER, both of the existing indexes do not support the local and join predicates on the table, as shown below.
对于cust_order_header表,现有的索引表不支持表上的本地和连接谓词,如下所示。
In a database, three tables represent m: m relationships: the two tables you'd expect (Book and Author), and a third join table (BookAuthor).
在数据库中,用三个表表示m: m关系:前两个表您已经知道了(Book和Author),第三个是一个连接表(BookAuthor)。
Indeed, the relationship between Book and Author goes beyond the simple join table.
确实如此,Book和Author之间的关系已经超出了简单连接表的范围。
You will start with the PERSONAL table and use a JOIN operation to get the professional information from the profession table.
您将以PERSONAL数据表开始,并且使用一个JOIN操作从PROFESSION数据表中获得职业信息。
The flight table is the join table, representing the complex relationship among the other tables. Listing 8 shows the fields in the flight table.
flight是连接表,表示其他表之间的复杂关系。
That is, the inner table of the join operation will be scanned eight times, once for each of the eight qualifying records from the outer input.
也就是说,联接操作的内部表将被扫描8次,来自外部输入的 8 个合格的记录每个都将被扫描一次。
The guideline specifies that table SECURITY should be the outer table in the join and the XML index SEC_INDUSTRY should be used to access the SECURITY table.
该准则指定应当将表SECURITY 作为连接中的外表,而XML索引 SEC_INDUSTRY 应当被用于访问 SECURITY 表。
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