我无法插入sql

Question

IMDB database Image to database structure FletNix

INSERT INTO FletNix_2.dbo.Movie_Cast
    SELECT cast(Pid AS int) AS person_id,
    cast(Mid AS int) AS movie_id,
    LEFT(Role, 255) AS role
    FROM MYIMDB.dbo.Imported_Cast

INSERT INTO FletNix_2.dbo.Movie_Directors
    SELECT cast(Did AS int) AS person_id,
    cast(Mid AS int) AS movie_id
    FROM MYIMDB.dbo.Imported_Movie_Directors

错误按摩：

消息 2627，级别 14，状态 1，第 71 行违反主键 约束“pk_moviecast”。无法在对象中插入重复键 'dbo.Movie_Cast'。重复键值为 ((Unknown))。

消息 547，级别 16，状态 0，第 77 行 INSERT 语句冲突 具有 FOREIGN KEY 约束“fk_directors_Person”。冲突 发生在数据库“FletNix_2”、表“dbo.Person”、列 'person_id'。

我知道我需要使用 distinct，但是当我这样做时

INSERT INTO FletNix_2.dbo.Movie_Cast
    SELECT cast(Pid AS int) AS person_id,
    cast(Mid AS int) AS movie_id,
    distinct LEFT(Role, 255) AS role
    FROM MYIMDB.dbo.Imported_Cast 

它给出了一个错误： 不同的语法不正确

当我在 SELECT 之后放置 distinct 时，我仍然得到一个错误：

违反主键约束“pk_moviecast”。无法插入 对象“dbo.Movie_Cast”中的重复键。重复键值为 （（未知））

与

INSERT 语句与 FOREIGN KEY 约束冲突 “fk_directors_Person”。数据库“FletNix_2”中发生冲突， 表“dbo.Person”，列“person_id”。

Answer 1

distinct 应该在select 之后

    INSERT INTO FletNix_2.dbo.Movie_Cast
    SELECT distinct cast(Pid AS int) AS person_id,
    cast(Mid AS int) AS movie_id,
    LEFT(Role, 255) AS role
    FROM MYIMDB.dbo.Imported_Cast 

因为你的角色列是主要的，所以它不必重复，所以我使用 row_number() 来生成唯一编号

     select 
    cast(Pid AS int) AS person_id,
    cast(Mid AS int) AS movie_id,        
    row_number()over( order by (select null)) as role
    FROM MYIMDB.dbo.Imported_Cast