There are several reasons why updating via join in MySQL can result in slow performance:
Large tables: if the tables being joined are very large, it can take a long time to update the joined result set.
Lack of indexes: if the tables being joined do not have appropriate indexes on the fields used for joining, the query may need to read all data to perform the join.
Complex conditions: if the join condition has complex expressions or functions, it can take longer to process the query.
Locking: updating via join can sometimes lock the table and prevent other queries from accessing it, which can slow down performance.
Server load: if the server is already under heavy load, updating via join can further slow down performance.
Asked: 2022-09-02 11:00:00 +0000
Seen: 11 times
Last updated: Jun 24 '22