如何删除postgresql列

如何删除postgresql列,postgresql,Postgresql,我的代码: drop table movie; CREATE TABLE movie ( imdib varchar NOT NULL, name varchar NOT NULL, year integer, rating varchar, votes varchar, runtime varchar, directors varchar, actors varchar, genres varchar ); COPY movies FROM '/home/max/Schreibtisc

我的代码:

drop table movie;

CREATE TABLE movie
(
imdib varchar NOT NULL,
name varchar NOT NULL,
year integer,
rating varchar,
votes varchar,
runtime varchar,
directors varchar,
actors varchar,
genres varchar
);


 COPY movies FROM '/home/max/Schreibtisch/imdb_top100.txt' (DELIMITER E'\t');

 COPY movies FROM '/home/max/Schreibtisch/imdb_top100t_2015-06-18.csv' (DELIMITER E'\t', FORMAT CSV);


SELECT actors, unnest(string_to_array(actors, '|')) AS Schauspieler from kinofilme;
SELECT directors, unnest(string_to_array(directors, '|')) AS Regisseure from movies;
SELECT genres, unnest(string_to_array(genres, '|')) AS Genrees from movies;
对最后3条语句的解释:体裁、演员和导演用“|”分隔(例如:体裁:动作|戏剧|惊悚片) 但我只想从体裁中获得一种体裁(例如从动作片、戏剧、惊悚片中获得唯一的动作片),这就是我使用unnest(字符串数组)的原因。问题是输出。当我使用
选择流派时,unnest(string_to_array(流派,“|”)作为电影的流派输出为:

类型(字符变化)\ uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu

  • 犯罪、戏剧、犯罪

  • 犯罪剧

  • 动作、戏剧、动作

  • 动作剧

  • 我想删除第一列“流派”,因为select语句不需要它。我只需要第二栏“Genrees”,其中显示了每种流派。如何删除第一个左科伦命名为“流派”或如何使其“消失”?提前感谢您。

    请使用此功能

    SELECT regexp_replace(genres,'\|.*','') AS Genrees from movies;
    
    这会回来的

    Crime
    Action
    

    对于您的示例

    您是否正在查找
    更改表格放置列
    ?我尝试了此操作,但无法创建表格,因为缺少“流派”。@Blnpwr我的答案有什么问题?