Question

我正在尝试将查询结果添加到现有表的列中。到目前为止，下面的查询找到了电线30公里范围内最近的变电站。

Select el1.id, 
   el1.geog4269.STAsText(), 
   (Select TOP 1 es.name from Test.dbo.electric_substations as es
    with (index(sidx_es))
    WHERE el1.geog4269.STDistance(es.geog) < 30000
    order by el1.geog4269.STDistance(es.geog)
    )As NearestElectricSubstation
    from Test.dbo.electric_lines AS el1;

现在我要做的是更新名为NNElines的表，该表具有以下模式：

CREATE TABLE NNElines
(  
id INT NOT NULL PRIMARY KEY,
Location geography NOT NULL,
Nearest_Esub varchar(50) NOT NULL
);

我想用结果中的el1.id更新id，使用el1.geog4269.STAsText（）更新id，使用NearestElectricSubstation更新Nearest_Esub。我正在尝试更新查询，但没有得到任何东西。任何帮助表示赞赏。谢谢

 Update Test.dbo.NNElines
SET id = el1.id,
 Location = el1.geog4269.STAsText()
From(
Select 
fnc.el1.id, 
fnc. el1.geog4269.STAsText()
From Test.dbo.electric_lines AS el1
   CROSS APPLY 
   (Select TOP 1 es.name from Test.dbo.electric_substations as es
    with (index(sidx_es))
    WHERE el1.geog4269.STDistance(es.geog) < 30000
    order by el1.geog4269.STDistance(es.geog)
    ) fnc
    --As NearestElectricSubstation
    --from Test.dbo.electric_lines AS el1;
    );

Answer 1

试试这个。更新表时可以使用JOIN。因此，我将您的查询加入了ID上的NNElines表，并使用查询中的相应值更新NNElines表。

UPDATE NNElines
SET a.location = b.geog4269.STAsText(),
  a.Nearest_Esub = b.NearestElectricSubstation
FROM NNElines a
JOIN
  (Select el1.id, 
    el1.geog4269.STAsText(), 
    (Select TOP 1 es.name from Test.dbo.electric_substations as es with (index(sidx_es))
       WHERE el1.geog4269.STDistance(es.geog) < 30000
       order by el1.geog4269.STDistance(es.geog)
    )As NearestElectricSubstation
  from Test.dbo.electric_lines AS el1) b 
ON a.id = b.id

使用查询结果SQL Server 2012更新现有表

1 个答案: