对于Microsoft SQL Server或PostgreSQL，您可能想要尝试此语法

SELECT constants FROM (VALUES ('foo@gmail.com')， ('bar@gmail.com')， ('baz@gmail.com')) AS MyTable(常量)

你也可以在这里查看一个SQL Fiddle: http://www.sqlfiddle.com/#!17/9eecb / 34703/0

在PostgreSQL中，你可以做:

SELECT  *
FROM    (
        VALUES
        (1, 2),
        (3, 4)
        ) AS q (col1, col2)

在其他系统中，只需使用UNION ALL:

SELECT  1 AS col1, 2 AS col2
-- FROM    dual
-- uncomment the line above if in Oracle
UNION ALL
SELECT  3 AS col1, 3 AS col2
-- FROM    dual
-- uncomment the line above if in Oracle

在Oracle, SQL Server和PostgreSQL中，您还可以生成任意行数的记录集(可通过外部变量提供):

SELECT  level
FROM    dual
CONNECT BY
        level <= :n

在Oracle中,

WITH    q (l) AS
        (
        SELECT  1
        UNION ALL
        SELECT  l + 1
        FROM    q
        WHERE   l < @n
        )
SELECT  l
FROM    q
-- OPTION (MAXRECURSION 0)
-- uncomment line above if @n >= 100

在SQL Server中，

SELECT  l
FROM    generate_series(1, $n) l

在PostgreSQL。

SELECT 1, 2, 3
UNION ALL SELECT 4, 5, 6
UNION ALL SELECT 7, 8, 9

在MySQL中，你可以这样做:values (1,2)， (3,4);

mysql> values (1,2), (3, 4);
+---+---+
| 1 | 2 |
+---+---+
| 1 | 2 |
| 3 | 4 |
+---+---+
2 rows in set (0.004 sec)

在MySQL 8中，也可以给列命名:

mysql> SELECT * FROM (SELECT 1, 2, 3, 4) AS dt (a, b, c, d);
+---+---+---+---+
| a | b | c | d |
+---+---+---+---+
| 1 | 2 | 3 | 4 |
+---+---+---+---+

SELECT * 
FROM DUAL 
CONNECT BY ROWNUM <= 9;

select (level - 1) * row_dif + 1 as a, (level - 1) * row_dif + 2 as b, (level - 1) * row_dif + 3 as c
    from dual 
    connect by level <= number_of_rows;

就像这样

select (level - 1) * 3 + 1 as a, (level - 1) * 3 + 2 as b, (level - 1) * 3 + 3 as c
    from dual 
    connect by level <= 3;