在SQL Server中,可以使用insert将行插入到表中。。SELECT语句:

INSERT INTO Table (col1, col2, col3)
SELECT col1, col2, col3 
FROM other_table 
WHERE sql = 'cool'

是否也可以使用SELECT更新表?我有一个包含这些值的临时表,并希望使用这些值更新另一个表。也许是这样的:

UPDATE Table SET col1, col2
SELECT col1, col2 
FROM other_table 
WHERE sql = 'cool'
WHERE Table.id = other_table.id

当前回答

另一种方法是使用派生表:

UPDATE t
SET t.col1 = a.col1
    ,t.col2 = a.col2
FROM (
SELECT id, col1, col2 FROM @tbl2) a
INNER JOIN @tbl1 t ON t.id = a.id

样本数据

DECLARE @tbl1 TABLE (id INT, col1 VARCHAR(10), col2 VARCHAR(10))
DECLARE @tbl2 TABLE (id INT, col1 VARCHAR(10), col2 VARCHAR(10))

INSERT @tbl1 SELECT 1, 'a', 'b' UNION SELECT 2, 'b', 'c'

INSERT @tbl2 SELECT 1, '1', '2' UNION SELECT 2, '3', '4'

UPDATE t
SET t.col1 = a.col1
    ,t.col2 = a.col2
FROM (
SELECT id, col1, col2 FROM @tbl2) a
INNER JOIN @tbl1 t ON t.id = a.id

SELECT * FROM @tbl1
SELECT * FROM @tbl2

其他回答

Use:

drop table uno
drop table dos

create table uno
(
    uid int,
    col1 char(1),
    col2 char(2)
)
create table dos
(
    did int,
    col1 char(1),
    col2 char(2),
    [sql] char(4)
)
insert into uno(uid) values (1)
insert into uno(uid) values (2)
insert into dos values (1,'a','b',null)
insert into dos values (2,'c','d','cool')

select * from uno 
select * from dos

或者:

update uno set col1 = (select col1 from dos where uid = did and [sql]='cool'), 
col2 = (select col2 from dos where uid = did and [sql]='cool')

OR:

update uno set col1=d.col1,col2=d.col2 from uno 
inner join dos d on uid=did where [sql]='cool'

select * from uno 
select * from dos

如果两个表中的ID列名相同,则只需将表名放在要更新的表之前,并为所选表使用别名,即:

update uno set col1 = (select col1 from dos d where uno.[id] = d.[id] and [sql]='cool'),
col2  = (select col2 from dos d where uno.[id] = d.[id] and [sql]='cool')

下面是另一个有用的语法:

UPDATE suppliers
SET supplier_name = (SELECT customers.name
                     FROM customers
                     WHERE customers.customer_id = suppliers.supplier_id)
WHERE EXISTS (SELECT customers.name
              FROM customers
              WHERE customers.customer_id = suppliers.supplier_id);

它使用“WHERE EXIST”检查它是否为空。

如果使用MySQL而不是SQL Server,语法为:

UPDATE Table1
INNER JOIN Table2
ON Table1.id = Table2.id
SET Table1.col1 = Table2.col1,
    Table1.col2 = Table2.col2

像其他人一样,必须指出MySQL或MariaDB使用不同的语法。它还支持非常方便的USING语法(与T/SQL相反)。INNER JOIN也是JOIN的同义词。因此,原始问题中的查询最好在MySQL中实现:

UPDATE
    Some_Table AS Table_A

JOIN
    Other_Table AS Table_B USING(id)

SET
    Table_A.col1 = Table_B.col1,
    Table_A.col2 = Table_B.col2

WHERE
    Table_A.col3 = 'cool'

我在其他答案中没有看到问题的答案,因此我的两分钱。(在PHP 7.4.0 MariaDB 10.4.10上测试)

使用别名:

UPDATE t
   SET t.col1 = o.col1
  FROM table1 AS t
         INNER JOIN 
       table2 AS o 
         ON t.id = o.id