MySQL deletes duplicate records in a table

Version: 5.0.22-community-nt.

1. Create a temporary table folder_tmp for the table folder

Create table folder_tmp as select * from folder group by serverIp, userId, name, path;

After grouping by serverIp, userId, name, and path, the data in front of the primary key id is left in the folder_tmp table.

2. Delete the original table

Drop table folder

3. rename a table

Alter table folder_tmp rename folder

4. Do not finish creating foreign keys and indexes and primary keys. Because the temporary table created in step 1 does not contain the Foreign keys, indexes, and primary keys of the original table.