人工验证清单是否完整,并且不包含应忽略的联结点。
Verify manually that the list is complete and does not include join points that should be omitted.
例如,当MQT中的两个或多个表定义了引用完整性关系并且联结谓词在它们自己的主键-外键列上时,就会出现这种情况。
For example, this might happen when two ore more of the tables in the MQT have a referential integrity relationship defined and the join predicate is on their primary key - foreign key columns.
完整的外部联结,将同时包括两边的资料表,即使该资料列在相关资料表中并没有相符项目。
Outer join in which all rows from the table represented on the right will be included, even if they do not have matches in the related table.
下面的概念图显示了两个集合中的完整项目,以及这两个集合彼此进行内部联结或左外部联结之后剩下的项目。
The following illustration shows a conceptual view of two sets and the elements within those sets that are included in either an inner join or a left outer join.
下面的概念图显示了两个集合中的完整项目,以及这两个集合彼此进行内部联结或左外部联结之后剩下的项目。
The following illustration shows a conceptual view of two sets and the elements within those sets that are included in either an inner join or a left outer join.
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