如何在 Oracle 中进行此查询

Question

我正在实现电影数据库，我在大学里有这个任务。 我有桌子：movies、people、movie_people、awards。 people 和 movies 都有字段 id of Award，可以是 NULL。 我不知道如何进行 SQL 查询，该查询将显示仅在有奖电影中演出的人员列表。你能帮我解决这个问题吗？

CREATE TABLE "LAB"."MOVIE" 
   (    "MOVIE_ID" NUMBER NOT NULL ENABLE, 
    "TITLE" VARCHAR2(219 BYTE) NOT NULL ENABLE, 
    "YEARMADE" DATE, 
    "COUNTRY" VARCHAR2(40 BYTE), 
    "RUNNINGTIME" NUMBER, 
    "LANGUAGE" VARCHAR2(40 BYTE), 
    "TAG_ID" NUMBER NOT NULL ENABLE, 
    "REVIEW_ID" NUMBER, 
    "AWARD_ID" NUMBER, 
     PRIMARY KEY ("MOVIE_ID")
  USING INDEX PCTFREE 10 INITRANS 2 MAXTRANS 255 
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)
  TABLESPACE "USERS"  ENABLE, 
     FOREIGN KEY ("TAG_ID")
      REFERENCES "LAB"."TAG" ("TAG_ID") ON DELETE CASCADE ENABLE, 
     FOREIGN KEY ("REVIEW_ID")
      REFERENCES "LAB"."REVIEW" ("REVIEW_ID") ON DELETE CASCADE ENABLE, 
     CONSTRAINT "AWARD_ID" FOREIGN KEY ("AWARD_ID")
      REFERENCES "LAB"."AWARD" ("AWARD_ID") ENABLE
   ) SEGMENT CREATION IMMEDIATE 
  PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)
  TABLESPACE "USERS" ;

  CREATE TABLE "LAB"."MOVIE_PEOPLE" 
   (    "MOVIE_ID" NUMBER NOT NULL ENABLE, 
    "PEOPLE_ID" NUMBER NOT NULL ENABLE, 
    "ROLE" VARCHAR2(60 BYTE) NOT NULL ENABLE, 
     FOREIGN KEY ("MOVIE_ID")
      REFERENCES "LAB"."MOVIE" ("MOVIE_ID") ON DELETE CASCADE ENABLE, 
     FOREIGN KEY ("PEOPLE_ID")
      REFERENCES "LAB"."PEOPLE" ("PEOPLE_ID") ON DELETE CASCADE ENABLE
   ) SEGMENT CREATION IMMEDIATE 
  PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)
  TABLESPACE "USERS" ;

  CREATE TABLE "LAB"."PEOPLE" 
   (    "PEOPLE_ID" NUMBER NOT NULL ENABLE, 
    "FAMILYNAME" VARCHAR2(40 BYTE) NOT NULL ENABLE, 
    "GIVENNAME" VARCHAR2(40 BYTE) NOT NULL ENABLE, 
    "GENDER" CHAR(1 BYTE) NOT NULL ENABLE, 
    "DATEOFBIRTH" DATE, 
    "TAG_ID" NUMBER, 
    "AWARD_ID" NUMBER, 
     PRIMARY KEY ("PEOPLE_ID")
  USING INDEX PCTFREE 10 INITRANS 2 MAXTRANS 255 
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)
  TABLESPACE "USERS"  ENABLE, 
     FOREIGN KEY ("TAG_ID")
      REFERENCES "LAB"."TAG" ("TAG_ID") ON DELETE CASCADE ENABLE, 
     FOREIGN KEY ("AWARD_ID")
      REFERENCES "LAB"."AWARD" ("AWARD_ID") ON DELETE CASCADE ENABLE
   ) SEGMENT CREATION IMMEDIATE 
  PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)
  TABLESPACE "USERS" ;

  CREATE TABLE "LAB"."AWARD" 
   (    "AWARD_ID" NUMBER NOT NULL ENABLE, 
    "TITLE" VARCHAR2(40 BYTE) NOT NULL ENABLE, 
    "YEAR" DATE NOT NULL ENABLE, 
     PRIMARY KEY ("AWARD_ID")
  USING INDEX PCTFREE 10 INITRANS 2 MAXTRANS 255 
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)
  TABLESPACE "USERS"  ENABLE
   ) SEGMENT CREATION IMMEDIATE 
  PCTFREE 10 PCTUSED 40 INITRANS 1 MAXTRANS 255 NOCOMPRESS LOGGING
  STORAGE(INITIAL 65536 NEXT 1048576 MINEXTENTS 1 MAXEXTENTS 2147483645
  PCTINCREASE 0 FREELISTS 1 FREELIST GROUPS 1 BUFFER_POOL DEFAULT FLASH_CACHE DEFAULT CELL_FLASH_CACHE DEFAULT)
  TABLESPACE "USERS" ;

Answer 1

实现此目的的一种方法是

WITH Q1 AS (SELECT DISTINCT p.PEOPLE_ID  -- people who appeared in award-winning movies
              FROM MOVIES m
              INNER JOIN AWARDS a
                ON a.AWARD_ID = m.AWARD_ID
              INNER JOIN MOVIE_PEOPLE mp
                ON mp.MOVIE_ID = m.MOVIE_ID
              INNER JOIN PEOPLE p
                ON p.PEOPLE_ID = mp.PEOPLE_ID),
     Q2 AS (SELECT DISTINCT p.PEOPLE_ID  -- people who appeared in non-award-winning movies
              FROM MOVIES m
              INNER JOIN MOVIE_PEOPLE mp
                ON mp.MOVIE_ID = m.MOVIE_ID
              INNER JOIN PEOPLE p
                ON p.PEOPLE_ID = mp.PEOPLE_ID
              WHERE m.AWARD_ID IS NULL)
SELECT Q1.PEOPLE_ID, p.*
  FROM Q1
  INNER JOIN PEOPLE p
    ON p.PEOPLE_ID = Q1.PEOPLE_ID
  LEFT OUTER JOIN Q2
    ON Q2.PEOPLE_ID = Q1.PEOPLE_ID
  WHERE Q2.PEOPLE_ID IS NULL

这里我们使用第一个 CTE (Q1) 来查找所有出现在获奖电影中的人，并使用第二个 CTE (Q2) 来查找所有出现在没有获奖的电影中的人。 （顺便说一句 - 你的设计有缺陷，因为电影可以赢得多个奖项，但没关系......）。在主查询中，我们将 Q1 中的所有人都外联到 Q2，只保留那些出现在 Q1 而不是 Q2 的人。

祝你好运。