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

从select语句更新的另一种方法:

UPDATE A
SET A.col = A.col,B.col1 = B.col1
FROM  first_Table AS A
INNER JOIN second_Table AS B  ON A.id = B.id WHERE A.col2 = 'cool'

其他回答

我以前使用过INSERT SELECT。对于那些想使用新东西的人来说,这里有一个类似的解决方案,但它要短得多:

UPDATE table1                                          // Table that's going to be updated.
LEFT JOIN                                              // Type of join.
    table2 AS tb2                                      // Second table and rename for easy.
ON
    tb2.filedToMatchTables = table1.fieldToMatchTables // Fields to connect both tables.
SET
    fieldFromTable1 = tb2.fieldFromTable2;             // Field to be updated on table1.

    field1FromTable1 = tb2.field1FromTable2,           // This is in the case you need to
    field1FromTable1 = tb2.field1FromTable2,           // update more than one field.
    field1FromTable1 = tb2.field1FromTable2;           // Remember to put ; at the end.

简单的方法是:

UPDATE
    table_to_update,
    table_info
SET
    table_to_update.col1 = table_info.col1,
    table_to_update.col2 = table_info.col2

WHERE
    table_to_update.ID = table_info.ID

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)

另一种尚未提及的可能性是将SELECT语句本身放入CTE,然后更新CTE。

WITH CTE
     AS (SELECT T1.Col1,
                T2.Col1 AS _Col1,
                T1.Col2,
                T2.Col2 AS _Col2
         FROM   T1
                JOIN T2
                  ON T1.id = T2.id
         /*Where clause added to exclude rows that are the same in both tables
           Handles NULL values correctly*/
         WHERE EXISTS(SELECT T1.Col1,
                             T1.Col2
                       EXCEPT
                       SELECT T2.Col1,
                              T2.Col2))
UPDATE CTE
SET    Col1 = _Col1,
       Col2 = _Col2;

这样做的好处是,首先很容易单独运行SELECT语句来检查结果的完整性,但如果源表和目标表中的列名称相同,则需要如上所述对列进行别名。

这也具有与专有UPDATE相同的限制。。。其他四个答案中显示了FROM语法。如果源表位于一对多连接的多方,则无法确定更新中将使用哪些可能匹配的连接记录(如果多次尝试更新同一行,MERGE会通过引发错误来避免此问题)。

SQLite3对我很有用,在INNER SELECT之后用SELECT更新行。

UPDATE clients
SET col1 = '2023-02-02 18:51:30.826621'
FROM (
      SELECT * FROM clients dc WHERE dc.phone NOT IN (
               SELECT do.phone FROM dclient_order do WHERE do.order_date > '2023-01-01' GROUP BY do.phone
               )
      ) NewTable
WHERE clients.phone = NewTable.phone;