获取按日期分组的行数

SELECT order_date, COUNT(*) as row_count
FROM orders
GROUP BY order_date

import mysql.connector

# 连接到数据库
cnx = mysql.connector.connect(user='username', password='password',
                              host='hostname',
                              database='database_name')

# 创建游标
cursor = cnx.cursor()

# 执行SQL查询
query = ("SELECT order_date, COUNT(*) as row_count "
         "FROM orders "
         "GROUP BY order_date")
cursor.execute(query)

# 获取结果集
for (order_date, row_count) in cursor:
    print(f"Date: {order_date}, Row Count: {row_count}")

# 关闭游标和数据库连接
cursor.close()
cnx.close()