问题描述
我有一个表,该表包含一列,该列包含一个包含其自身ID的字符串。 如何使用单个sql语句插入新行?
id| URL
--|----------------------
1|"http://example.com/1"
2|"http://example.com/2"
3|"http://example.com/3"
我需要类似的东西
NEXT_ID = SELECT nextval('table_name_id_seq');
insert into table_name (id,name) values (NEXT_ID,'http://example.com/' + NEXT_ID) returning *
https://www.db-fiddle.com/f/3NwLNBirN7mHKpDk9NyHSy/1
解决方法
一个选项是先在子查询中选择下一个序列:
insert into test(id,url)
select id,'http://example.com/' || id::text
from (select nextval('test_id_seq') as id) x;
您还可以使用计算列代替整洁的插入代码:
create table test(
id SERIAL,url text,new_url text generated always as (url || id::text) stored
);
insert into test(url) values ('http://example.com/');
给你:
| id | url | new_url |
| --- | ------------------- | -------------------- |
| 1 | http://example.com/ | http://example.com/1 |