以數據庫術語來說,當我添加一個新的外鍵時,爲該外鍵插入一條記錄並更新現有記錄,該過程稱爲什麼?我的目標是能夠更有效地找到答案。什麼是將一個新的關係添加到名爲?
//create temporary linking key
alter table example add column example_foreign_key int unsigned null;
//contains more fields
insert into example_referenced_table (example_id, ...)
select id, ...
from example
join ...;
//link with the table
update example join example_referenced_table on example_id = example.id
set example.example_foreign_key = example_referenced_table.id;
//drop linking key
alter table example_referenced_table drop column example_id;
爲什麼downvote? –