import MySQLdb
from app import settings
conn = MySQLdb.connect(host=settings.DATABASE_HOST, user=settings.DATABASE_USER,passwd=settings.DATABASE_PASSWORD, db=settings.DATABASE_NAME, charset='utf8')
d_command = 'DELETE FROM news WHERE created_at <= DATE_SUB(NOW(), INTERVAL 7 DAY);'
cursor = conn.cursor(MySQLdb.cursors.DictCursor) #这个是不是必须得有的？
cursor.execute(d_command)
cursor.close()
conn.close()
DATE_SUB函数
DATE_SUB() 函数：从日期减去指定的时间间隔。
语法：DATE_SUB(date,INTERVAL expr type)
date 参数是合法的日期表达式。expr 参数是您希望添加的时间间隔。
type 参数可以是下列值：
| Type 值 |
|---|
| MICROSECOND |
| SECOND |
| MINUTE |
| HOUR |
| DAY |
| WEEK |
| MONTH |
| QUARTER |
| YEAR |
| SECOND_MICROSECOND |
| MINUTE_MICROSECOND |
| MINUTE_SECOND |
| HOUR_MICROSECOND |
| HOUR_SECOND |
| HOUR_MINUTE |
| DAY_MICROSECOND |
| DAY_SECOND |
| DAY_MINUTE |
| DAY_HOUR |
| YEAR_MONTH |