MYSQL

DATE_ADD

SELECT `tid`, DATE_ADD(`send_goods_at`, INTERVAL 8 HOUR)  FROM `taobao_orders` WHERE `tid` IN ('166766380536047', '166789906978402')

Mysql Remove Duplicate Data or Rows With DISTINCT

delete from table1
USING table1, table1 as vtable
WHERE (NOT table1.ID=vtable.ID)
AND (table1.field_name=vtable.field_name)

1. Here you tell mysql that there is a table1.
2. Then you tell it that you will use table1 and a virtual table with the values of table1.
3. This will let mysql not compare a record with itself!
4. Here you tell it that there shouldn’t be records with the same field_name.