SELECT查询从一个表中返回一行，所有值都设置为Null [英] SELECT query to return a row from a table with all values set to Null

问题描述

我需要进行查询，但是每个字段的值都为空。 Gordon Linoff给了我这个需求的线索：
SQL空查询结果
，它是：

I need to make a query but get the value in every field empty. Gordon Linoff give me the clue to this need here: SQL Empty query results which is:

select t.*
from (select 1 as val
     ) v left outer join
     table t
     on 1 = 0;

这个查询在PostgreSQL上完美的发现，但是试图在Microsoft Access中执行它时会出错，它说1 = 0表达式不被承认。

This query wors perfectly on PostgreSQL but gets an error when trying to execute it in Microsoft Access, it says that 1 = 0 expression is not admitted. How could it be fixed to work on microsoft access?

请问，

推荐答案

如果表的数值主键列的值为非负数，那么以下查询将在Access中运行。主键字段为[ID]。

If the table has a numeric primary key column whose values are non-negative then the following query will work in Access. The primary key field is [ID].

SELECT t2.*
FROM
    myTable AS t2
    RIGHT JOIN
    (
        SELECT TOP 1 (ID * -1) AS badID 
        FROM myTable AS t1
    ) AS rowStubs
        ON t2.ID = rowStubs.badID

这是使用Access 2010进行测试。

This was tested with Access 2010.

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