考虑这个表在MySQL

create table numbers (number int);
insert into numbers values (3), (2), (9);
select * from numbers;

+--------+
| number |
+--------+
|      3 |
|      2 |
|      9 |
+--------+

是否有一个简单的查询来生成具有以下列的表

从1到10的数字
如果表号中存在数字，则为1，否则为0

我想您必须创建一个数字序列才能执行此操作。如果可能的话，我想创建一个这样的序列而不将其存储在数据库中。

相关问题：是否有一个选择查询生成一个从1到10（或100或1000）的数字序列？

mysql sequence

— j
source

在MariaDB中

MariaDB具有SEQUENCE存储引擎。因此，如果您使用的是MariaDB，则所有序列问题都已结束（或刚刚开始）。

10个数字的序列

select * from seq_1_to_10;

不使用表

10个数字的序列

select * from
(select 0 x union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) A;

100个数字的序列

select (t*10+u+1) x from
(select 0 t union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) A,
(select 0 u union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) B
order by x;

1000个数字的序列

select (h*100+t*10+u+1) x from
(select 0 h union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) A,
(select 0 t union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) B,
(select 0 u union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) C
order by x;

10000个数字的序列

select (th*1000+h*100+t*10+u+1) x from
(select 0 th union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) A,
(select 0 h union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) B,
(select 0 t union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) C,
(select 0 u union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) D
order by x;

使用表格

10个数字的序列

use test
drop table if exists seq10;
create table seq10
(x int not null auto_increment primary key);
insert into seq10 values (),(),(),(),(),(),(),(),(),();
select * from seq10;

100个数字的序列

use test
drop table if exists seq100;
create table seq100
(x int not null auto_increment primary key);
insert into seq100 values (),(),(),(),(),(),(),(),(),();
insert into seq100 values (),(),(),(),(),(),(),(),(),();
insert into seq100 values (),(),(),(),(),(),(),(),(),();
insert into seq100 values (),(),(),(),(),(),(),(),(),();
insert into seq100 values (),(),(),(),(),(),(),(),(),();
insert into seq100 select x + 50 from seq100;
select * from seq100;

1000个数字的序列

use test
drop table if exists seq1000;
create table seq1000
(x int not null auto_increment primary key);
insert into seq1000 values ();
set @p= -1;
set @p=@p+1; insert into seq1000 select x+power(2,@p) from seq1000 where (x+power(2,@p)) <= 1000;
set @p=@p+1; insert into seq1000 select x+power(2,@p) from seq1000 where (x+power(2,@p)) <= 1000;
set @p=@p+1; insert into seq1000 select x+power(2,@p) from seq1000 where (x+power(2,@p)) <= 1000;
set @p=@p+1; insert into seq1000 select x+power(2,@p) from seq1000 where (x+power(2,@p)) <= 1000;
set @p=@p+1; insert into seq1000 select x+power(2,@p) from seq1000 where (x+power(2,@p)) <= 1000;
set @p=@p+1; insert into seq1000 select x+power(2,@p) from seq1000 where (x+power(2,@p)) <= 1000;
set @p=@p+1; insert into seq1000 select x+power(2,@p) from seq1000 where (x+power(2,@p)) <= 1000;
set @p=@p+1; insert into seq1000 select x+power(2,@p) from seq1000 where (x+power(2,@p)) <= 1000;
set @p=@p+1; insert into seq1000 select x+power(2,@p) from seq1000 where (x+power(2,@p)) <= 1000;
set @p=@p+1; insert into seq1000 select x+power(2,@p) from seq1000 where (x+power(2,@p)) <= 1000;
select * from seq1000;

任何数字的顺序（例如：350万）

use test
drop table if exists seq;
create table seq
(x int not null auto_increment primary key);
insert into seq values ();
set @maxseq = 3500000;
set @p = -1;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
set @p=@p+1; insert into seq select x+power(2,@p) from seq where (x+power(2,@p)) <= @maxseq;
select max(x),count(x) from seq;

您的实际问题

使用序列0..9，您将序列与表格左连接

select A.number,1-ISNULL(B.number) present from
(select 0 number union select 1 union select 2 union select 3 union select 4 union
select 5 union select 6 union select 7 union select 8 union select 9) A
left join numbers B using (number);

您的带有新查询的示例数据

mysql> drop table numbers;
Query OK, 0 rows affected (0.01 sec)

mysql> drop table if exists numbers;
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> create table numbers (number int);
Query OK, 0 rows affected (0.02 sec)

mysql> insert into numbers values (3), (2), (9);
Query OK, 3 rows affected (0.01 sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> select A.number,1-ISNULL(B.number) present from
    -> (select 0 number union select 1 union select 2 union select 3 union select 4 union
    -> select 5 union select 6 union select 7 union select 8 union select 9) A
    -> left join numbers B using (number);
+--------+---------+
| number | present |
+--------+---------+
|      0 |       0 |
|      1 |       0 |
|      2 |       1 |
|      3 |       1 |
|      4 |       0 |
|      5 |       0 |
|      6 |       0 |
|      7 |       0 |
|      8 |       0 |
|      9 |       1 |
+--------+---------+
10 rows in set (0.00 sec)

mysql>

试试看！！！

— 罗兰多·MySQLDBA
source

在这里使用函数会不会简单得多？一个自定义函数，返回的范围与您提到的MariaDB一样，range(10,20)

— azerafati

@Rolando-这仍然是最好的方法吗？问一个朋友。

— Max Vernon

@MaxVernon在MariaDB之外，这些几乎是我无需使用函数即可创建序列的方式。不使用表可以省去创建磁盘I / O来创建序列的麻烦。

— RolandoMySQLDBA

@MaxVernon使用新发布的GA版本的MySQL 8.0（以及一年前发布的MariaDB 10.2 GA版本），您可以使用递归CTE，这使此过程变得更加简单。好吧，MariaDB序列存储引擎是最简单的，但是递归CTE可能是MySQL和需要同时在MySQL和MariaDB上运行的查询的一种方式。

— dbdemon

使用MySQL 8.0，MariaDB 10.2和更高版本，您可以使用递归CTE，因此：

WITH RECURSIVE nums AS (
    SELECT 1 AS value
    UNION ALL
    SELECT value + 1 AS value
    FROM nums
    WHERE nums.value <= 9
)
SELECT *
FROM nums;

您显然可以对其进行修改，以使用您选择的起始值，步长和结束值。

至于第二个问题，那么扩展上面的内容就变得微不足道了（从罗纳尔多的部分答案中得到启发）：

WITH RECURSIVE nums AS (
    SELECT 1 AS value
    UNION ALL
    SELECT value + 1 AS value
    FROM nums
    WHERE nums.value <= 9
)
SELECT nums.value, 1-ISNULL(numbers.number) present
FROM nums
  LEFT JOIN numbers ON numbers.number = nums.value
ORDER BY nums.value;

编辑：

MariaDB 10.3引入了序列对象（如SQL标准中所定义，例如在Oracle RDBMS中所见）。由于这些值存储在数据库中，因此对这个特定问题没有帮助，但是该功能在与序列相关的其他用例中可能很有用。

— dbdemon
source

如何在MySQL中生成序列

在MariaDB中

不使用表

使用表格

您的实际问题

试试看 ！！！

试试看！！！