刪除特定行，所有值匹配

Question

說我有一個表

SELECT * INTO MyTable FROM (
    VALUES ('col1_a', 'col2_a', 'col3_a', 'coln_a'), 
     ('col1_b', 'col2_b', 'col3_b', 'coln_b'), 
     ('col1_c', 'col2_c', 'col3_c', 'coln_c') 
) t (col1, col2, col3, coln) 

我只想刪除與每一個列值相匹配的行我的具體（考慮行高度相似只有一個或兩列不同）

我當然可以寫

DELETE MyTable WHERE col1='col1_a' AND col2='col2_a' AND col3='col3_a' AND coln='coln_a' 
DELETE MyTable WHERE col1='col1_b' AND col2='col2_b' AND col3='col3_b' AND coln='coln_b' 

但是那太煩人了。我想知道是否可以通過簡單列出值來方便地編寫它？我試過這個

DELETE MyTable FROM (
    VALUES ('col1_a', 'col2_a', 'col3_a', 'coln_a'), 
     ('col1_b', 'col2_b', 'col3_b', 'coln_b') 
) t (col1, col2, col3, coln) 

但這只是刪除了MyTable中的所有行，請幫忙。

Answer 1

您可以在DELETE語句中使用INNER JOIN：

DELETE t1 
FROM MyTable t1 
INNER JOIN (
    SELECT * 
    FROM (VALUES 
     ('col1_a', 'col2_a', 'col3_a', 'coln_a'), 
     ('col1_b', 'col2_b', 'col3_b', 'coln_b') 
    )AS a(col1, col2, col3, coln) 
) t2 
    ON t2.col1 = t1.col1 
    AND t2.col2 = t1.col2 
    AND t2.col3 = t1.col3 

---

正如評論說Frisbee，你可以刪除SELECT *：

DELETE t1 
FROM MyTable t1 
INNER JOIN (
    VALUES 
     ('col1_a', 'col2_a', 'col3_a', 'coln_a'), 
     ('col1_b', 'col2_b', 'col3_b', 'coln_b')  
) AS t2(col1, col2, col3, coln) 
    ON t2.col1 = t1.col1 
    AND t2.col2 = t1.col2 
    AND t2.col3 = t1.col3