Question

我有一个表“人”，一个关联表“person_vaccination”和一个表“疫苗接种”。

我想找到那些缺少疫苗接种的人，但到目前为止我只有在我有身份证时才能上班。

SELECT vac.VACCINATION_Name
FROM VACCINATION vac
WHERE vac.VACCINATION_NUMBER NOT IN
(SELECT v.VACCINATION_NUMBER
FROM  PERSON per
Join PERSON_VACCINATION pv ON per.PERSON_NUMBER = pv.PERSON_NUMBER
JOIN VACCINATION v ON pv.VACCINATION_NUMBER = v.VACCINATION_NUMBER
WHERE per.PERSON_NUMBER = 6)

它工作正常，但我如何让所有人错过接种疫苗？（例如： 555，疫苗接种1 555，疫苗接种2 666，疫苗接种1）

Answer 1

SQL Fiddle

Oracle 11g R2架构设置：

CREATE TABLE VACCINATION ( VACCINATION_NUMBER, VACCINATION_NAME ) AS
          SELECT 1, 'Vac 1' FROM DUAL
UNION ALL SELECT 2, 'Vac 2' FROM DUAL
UNION ALL SELECT 3, 'Vac 3' FROM DUAL
UNION ALL SELECT 4, 'Vac 4' FROM DUAL;

CREATE TABLE PERSON_VACCINATION ( VACCINATION_NUMBER, PERSON_NUMBER ) AS
          SELECT 1, 1 FROM DUAL
UNION ALL SELECT 2, 1 FROM DUAL
UNION ALL SELECT 3, 1 FROM DUAL
UNION ALL SELECT 4, 1 FROM DUAL
UNION ALL SELECT 1, 2 FROM DUAL
UNION ALL SELECT 2, 2 FROM DUAL
UNION ALL SELECT 3, 2 FROM DUAL;

CREATE TABLE PERSON ( PERSON_NUMBER, PERSON_NAME ) AS
          SELECT 1, 'P1' FROM DUAL
UNION ALL SELECT 2, 'P2' FROM DUAL
UNION ALL SELECT 3, 'P3' FROM DUAL;

查询1 ：

SELECT p.PERSON_NAME,
       v.VACCINATION_NAME
FROM   VACCINATION v
       CROSS JOIN
       PERSON p
WHERE  NOT EXISTS ( SELECT 1
                    FROM   PERSON_VACCINATION pv
                    WHERE  pv.VACCINATION_NUMBER = v.VACCINATION_NUMBER
                    AND    pv.PERSON_NUMBER = p.PERSON_NUMBER )
ORDER BY p.PERSON_NAME,
         p.PERSON_NUMBER,
         v.VACCINATION_NAME,
         v.VACCINATION_NUMBER

<强> Results ：

| PERSON_NAME | VACCINATION_NAME |
|-------------|------------------|
|          P2 |            Vac 4 |
|          P3 |            Vac 1 |
|          P3 |            Vac 2 |
|          P3 |            Vac 3 |
|          P3 |            Vac 4 |

Answer 2

不应使用INNER JOIN，而应使用LEFT JOIN。

请看一下这个链接：http://www.w3schools.com/sql/sql_join_left.asp

Answer 3

如果您完全没有接种疫苗的人，那么您可以在PERSON和PERSON_VACCINATION之间使用LEFT OUTER JOIN，然后找到PERSON_VACCINATION列为NULL的所有条目。

SELECT PERSON_NUMBER
FROM PERSON P
LEFT OUTER JOIN
PERSON_VACCINATION PV
ON P.PERSON_NUMBER = PV.PERSON_NUMBER
WHERE PV.PERSON_NUMBER IS NULL

如果您不熟悉LEFT OUTER JOIN，它会尝试在PERSON_VACCINATION中为PERSON中的每一行找到匹配的行。如果没有匹配的行，它会在结果集中保留PERSON行，并在PERSON_VACCINATION表中显示所有列的NULL值。

如果您正在寻找他们没有的人员和疫苗清单，那么@ MT0的答案是正确的。您需要创建一个包含PERSON和VACCINATION（交叉连接）的所有可能组合的结果集，然后检查PERSON_VACCINATION中实际存在哪些组合。任何不存在的条目都是您缺少的疫苗接种。

SQL - 从关联中选择第二个表中没有的内容

3 个答案: