如何使用复合键进行SELECT? [英] how to do a SELECT with a composite key?

问题描述

我有一个带有复合键的表，我想用该键进行SELECT查询，有没有一种方法可以在复合键上放置名称或进行查询而不必添加AND

I have a table with a composite key, and I want to do my SELECT query with that key, is there a way to put a name to the composite key or to do the query without having to add an AND

比方说:

SELECT * FROM MyTable WHERE PRIMARY KEY = 12345

将该主键作为复合键

推荐答案

不，没有SELECT * FROM MyTable WHERE PRIMARY KEY ='PrimaryKeyName'的概念.换句话说，谓词(WHERE子句)不允许这样做.您将需要列出谓词中的复合主键中包含的所有列.

No, there is no concept of SELECT * FROM MyTable WHERE PRIMARY KEY = 'PrimaryKeyName'. In other words, the predicate (WHERE clause) does not allow for this. You will need to list all columns that are contained within the composite primary key in the predicate.

一个潜在的解决方案是构建一个表，该表存储事实表的所有主键组合.您可以将一个标识字段添加到该表，并使其成为表上的外键约束.然后，您的谓词使用单个外键列.

A potential solution is to build a table that stores all primary key combinations for the fact table. You can add an identity field to that table and make it a foreign key constraint on your table. Then, your predicate uses the single foreign key column.

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