SQL选择具有多个值的行-SQLSelectingrowswithmultiplevalues

I have these 2 tables:

我有这两个表：

Table SW_ITEM:

表SW_ITEM：

ID  SWID  ITEM_ID
1    1      99
2    2      99
3    5      99
4    2      100
5    1      100
6    1      101
7    2      102

Table ITEM:

表项目：

  ID   FILENAME
  99      abc
  100     def
  101     geh
  102     ijk

column ITEM_ID is a foreign key to the column ID of table ITEM.

列ITEM_ID是表ITEM的列ID的外键。

So I want all filenames which have the SWID "1" AND "2" (that would be ITEMID 99 and 100, so their filenames are "abc" and "def")

所以我想要所有SWID为“1”和“2”的文件名（即ITEMID 99和100，所以他们的文件名是“abc”和“def”）

Here I have to say that it is possible that ITEM_ID has more than one entry with the same SWID, so I cannot use this SQL:

在这里我不得不说ITEM_ID有可能有多个具有相同SWID的条目，所以我不能使用这个SQL：

SELECT ITEM_ID FROM SW_ITEM
WHERE SWID  IN (1,2) 
GROUP BY ITEM_ID
HAVING COUNT(ITEM_ID) = 2

So is there any other possibility to get all entries which have the SWID 1 and 2 (creating a join for every SWID is also not an option - because with many entries it would be really slow)

那么还有其他任何可能获得具有SWID 1和2的条目（为每个SWID创建连接也不是一个选项 - 因为有很多条目它会非常慢）

Kind regards

亲切的问候

2 个解决方案

SELECT ITEM_ID FROM SW_ITEM
WHERE  SWID IN (1,2) 
GROUP  BY ITEM_ID
HAVING COUNT(DISTINCT SWID) = 2;

SELECT ITEM_ID, FILENAME
FROM   ITEM JOIN SW_ITEM ON ITEM.ID = SW_ITEM.ITEM_ID
WHERE  SWID IN (1,2) 
GROUP  BY ITEM_ID
HAVING COUNT(DISTINCT SWID) = 2;

SELECT person_id, 
(ROW_NUMBER () OVER (PARTITION BY pers_email ORDER BY pers_name) person_count  
from pers_table
WHERE person_count > 2;