在带有差分列的postgres中创建视图

问题描述

我有一个唯一的表，在同一列中包含用于人员和组织的混合数据，只有一个只有1个字母的字段可以设置数据引用。

示例

id|type | surname of person/organization | name of person/address of organization | person sex/organization fiscal code
 1|   P | GATES                          | BILL                                   | M
 2|   O | GOOGLE                         | PALO ALTO                              | 04340349204920
 3|   P | DOE                            | JENNIFER                               | F
...etc....

我想在Postgres中创建一个视图，以按引用类型（字母）组织和分隔信息，像这样

id|type|surname|name      |sex|organization|address    |fiscal code
 1| P  | GATES | BILL     | M |            |           |         
 2| O  |       |          |   | GOOGLE     | PALO ALTO | 04340349204920
 3| P  | DOE   | JENNIFER | F |            |           | 

我认为这对我来说应该很简单，但我被困住了。

解决方法

您可以使用大小写表达式：

create view myview (surname,name,sex,orga,address,fiscal_code) as
select
    id,type,case when type = 'P' then surname_or_orga    end as surname,case when type = 'P' then name_or_address    end as name,case when type = 'P' then sex_or_fiscal_code end as sex,case when type = 'O' then surname_or_orga    end as orga,case when type = 'O' then name_or_address    end as address,case when type = 'O' then sex_or_fiscal_code end as fiscal_code
from mytable