Mysql 如果情况 1 进行查询，如果情况 2 进行另一次查询

Question

I need a query for SCD2 in MySQL using:

DATA STRUCTURE: id, data, start_date, end_date

if the record_id exist:

-update the record's end_date,

-and create a new record with the new data

else:

-insert a new record.

Can I use MySQL CASE to this?

Answer 1

You dont need an end-date to store historic data; Whenever you want to store a new address, you simply add it with the start-date. You retrieve history by SELECT * FROM table ORDER BY start-date Or just the last address by SELECT * FROM table ORDER BY start-date DESC LIMIT 1