PostgreSQL 行转列、列转行字符串函数

列子：

1、行转列

select regexp_split_to_table(permit_type,',') as code from food_perfect_factor a where a.permit_number = 'SC20152272518392'

2、列转行

select string_agg(a.code,',') from (select regexp_split_to_table(permit_type,',') as code from food_perfect_factor a where a.permit_number = 'SC20152272518392') a