sql - 更新表变量

Question

我有一个表变量 @searchResult :

DECLARE @searchResult TABLE (
    [name_template] NVARCHAR(50),
    [record_id] INT,
    [record_name] NVARCHAR(50)
);

和表[records] :

CREATE TABLE [records] (
    [record_id] INT IDENTITY(1, 1) PRIMARY KEY,
    [record_name] NVARCHAR(50)
)

@searchResult包含 [name_template] 的记录只填。我想用最新的 [record_id] 更新它和 [record_name]来自 [records]匹配的表 [name_template] .

我试过以下 SQL 查询但没有成功:

UPDATE @searchResult
SET [record_id] = r.[record_id], [record_name] = r.[record_name]
FROM (
    SELECT TOP 1
          r.[record_id]
        , r.[record_name]
    FROM [records] AS r
    WHERE r.[record_name] LIKE [name_template]
    ORDER BY r.[record_id] DESC
) AS r;

错误信息:

Invalid column name 'name_template'.

更新的正确语法是什么 @searchResult具有所需的值？

Answer 1

你需要做一个 CROSS APPLY在 table 上。

UPDATE @searchResult
SET [record_id] = r.[record_id], 
    [record_name] = r.[record_name]
FROM @searchResult SR
CROSS APPLY (
    SELECT TOP 1 *
    FROM [records]
    WHERE [record_name] LIKE [name_template]   -- Your wish, but do you really need LIKE matching??
    ORDER BY [record_id] DESC
) AS r;