文章目录
cursor游标简介
游标：执行sql语句后，取出返回结果的接口。提供游标接口，借助游标一行一行取出数据，直到最后一行，游标为空。
一、案例说明
图示说明：
如果不使用游标功能，直接使用select查询，会一次性将结果集打印到屏幕上，你无法针对结果集做第二次编程
案例：student表
使用fetchall()方法，获取SQL查询结果集中的数据
db = pymysql.connect(host='localhost',user='root',db='huangwei',
password='123456',port=3306,charset='utf8')
cursor = db.cursor()
cursor.execute('select sname,ssex from student')
aa = cursor.fetchall()
# print(aa)
for a,b in aa:
if b == "女":
a = "我叫{}，我是一个学生！".format(a)
print(a)
db.close()
结果如下：
二、使用步骤
① 连接数据库，创建一个数据库对象
db = pymysql.connect(host='localhost',user='root',db='huangwei',
password='123456',port=3306,charset='utf8')
② 开启游标功能，创建游标对象
# 这里使用的是数据库对象db中的cursor()方法，
cursor = db.cursor()
③ 使用execute()方法，执行SQL语句
cursor.execute('select sname,ssex from student')
④ 使用fetchone()或fetchall()，fetchmany(n)获取数据
# 一次性获取一条数据
a = cursor.fetchone()
# 一次性获取所有数据
a = cursor.fetchall()
# 获取n条数据
a = cursor.fetchmany(n)
⑤ 断开数据库，释放资源
db.close()
三、源码
def sqlMigrate():
source_db = cx_Oracle.connect('********', '********', '133.0.**.**:**/xydb') # 源库
target_db = pymysql.connect('10.37.6.**', 'root', '********', 'enterprise_internet') # 目标库
# 2.创建游标
cur_select = source_db.cursor() # 源库查询对象
cur_insert = target_db.cursor() # 目标库插入对象
# 3.执行SQL
sql_select_product = "SELECT product_id, product_name, flag1, flag2 FROM xy_report.ldl_zq_zw_hlw_product "
cur_select.execute(sql_select_product)
# 获取源表有多少个列
desc = cur_select.description
col_len = len(desc)
# MySQL批量插入语法是 insert into tb_name values(%s,%s,%s,%s)
val_str = ''
for i in range(1, col_len):
val_str = val_str + '%s' + ','
val_str += '%s'
# 拼接insert into 目标表 values #目标表插入语句
sql_insert_product = 'insert into bossInfo_product(product_id, product_name,flag_provinces,flag_hlzw)' \
+ ' values(' + val_str + ')'
print('开始执行product:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
cur_select.execute(sql_select_product) # 执行
while True:
# 每次获取100行，由cur_select.arraysize值决定，MySQL fetchmany 返回的是 tuple 数据类型 所以用list做类型转换
rows = list(cur_select.fetchmany(10))
# 批量插入每次100行，需要注意的是 rows 必须是 list [] 数据类型
cur_insert.executemany(sql_insert_product, rows)
target_db.commit() # 提交
if not rows:
break # 中断循环
print('执行成功product:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
# order_status
sql_select_order_status = "select attr_value,attr_value_name,attr_value_desc " \
"from cpcp_spec.attr_value@to_crm30db where attr_id ='9990010422'"
sql_insert_order_status = 'insert into bossInfo_order_status(order_value, value_name,value_desc)' \
+ ' values(%s,%s,%s)'
print('开始执行order_status:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
cur_select.execute(sql_select_order_status) # 执行
while True:
# 每次获取100行，由cur_select.arraysize值决定，MySQL fetchmany 返回的是 tuple 数据类型 所以用list做类型转换
rows = list(cur_select.fetchmany(10))
# 批量插入每次100行，需要注意的是 rows 必须是 list [] 数据类型
cur_insert.executemany(sql_insert_order_status, rows)
target_db.commit() # 提交
if not rows:
break # 中断循环
# Service_Offer
print('开始执行Service_Offer:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
sql_select_service_offer = "SELECT service_offer_id,service_offer_name from CPCP_SPEC.SERVICE_OFFER@to_crm30db"
sql_insert_service_offer = 'insert into bossInfo_service_offer(service_offer_id, service_offer_name)' \
+ ' values(%s,%s)'
cur_select.execute(sql_select_service_offer) # 执行
rows = list(cur_select.fetchall())
cur_insert.executemany(sql_insert_service_offer, rows)
target_db.commit() # 提交
# common_region
print('开始执行common_region:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
sql_select_common_region = "select common_region_id, par_region_id, region_nbr, region_name " \
"from cpcp_spec.common_region@to_crm30db where lan_id = 8420600"
sql_insert_common_region = 'insert into bossInfo_common_region(common_region_id, par_region_id, region_nbr, region_name )' \
+ ' values(%s,%s,%s,%s)'
cur_select.execute(sql_select_common_region) # 执行
rows = list(cur_select.fetchall())
cur_insert.executemany(sql_insert_common_region, rows)
target_db.commit() # 提交
cur_select.close()
cur_insert.close()
source_db.close()
target_db.close()
print('执行成功:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
def sqlMigrate_boss():
source_db = cx_Oracle.connect('********', '********', '133.0.**.**:**/xydb') # 源库
target_db = pymysql.connect('10.37.6.**', 'root', '********', 'enterprise_internet') # 目标库
# 2.创建游标
cur_select = source_db.cursor() # 源库查询对象
cur_insert = target_db.cursor() # 目标库插入对象
# 3.执行SQL
sql_select_prod_inst = "SELECT distinct prod_inst_id,order_item_id,acc_num,address_desc,prod_id," \
"owner_cust_id,use_cust_id,region_id,create_date " \
"FROM ORD_SO.ORD_PROD_INST@to_crm30db where prod_id in (" \
"select product_id from lh_zq_lx_product) " \
"and lan_id = '8420600'" \
"and to_char(create_date, 'yyyy-mm-dd') = to_char(sysdate - 30, 'yyyy-mm-dd')"
cur_select.execute(sql_select_prod_inst)
# 获取源表有多少个列
desc = cur_select.description
col_len = len(desc)
# MySQL批量插入语法是 insert into tb_name values(%s,%s,%s,%s)
val_str = ''
for i in range(1, col_len):
val_str = val_str + '%s' + ','
val_str += '%s'
# 拼接insert into prod_inst 目标表 values
sql_insert_prod_inst = 'insert into bossInfo_prod_inst(prod_inst_id,order_item_id,acc_num,address_desc,prod_id,' \
'owner_cust_id,use_cust_id,region_id,create_date)' \
+ ' values(' + val_str + ')'
# 是否重复
sql_insert_prod_inst_r = 'select prod_inst_id,acc_num from bossInfo_prod_inst'
# insert into order_item 目标表 values
sql_insert_order_item = 'insert into bossInfo_order_item(prod_inst_id,order_item_id,acc_num) values(%s,%s,%s)'
sql_insert_order_item_r = 'select prod_inst_id,order_item_id from bossInfo_order_item'
# insert into contact_cust_info 目标表 values
sql_insert_contact_cust_info = 'insert into bossInfo_contact_cust_info(owner_cust_id, use_cust_id) values(%s,%s)'
sql_insert_contact_cust_info_r = 'select owner_cust_id,use_cust_id from bossInfo_contact_cust_info'
# insert into contact_manager_info 目标表 values
sql_insert_contact_manager_info = 'insert into bossInfo_contact_manager_info(prod_inst_id,acc_num ) values(%s,%s)'
sql_insert_contact_manager_info_r = 'select prod_inst_id,acc_num from bossInfo_contact_manager_info'
print('开始执行prod_inst:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
cur_select.execute(sql_select_prod_inst)
while True:
# 每次获取100行，由cur_select.arraysize值决定，MySQL fetchmany 返回的是 tuple 数据类型 所以用list做类型转换
rows = list(cur_select.fetchmany(1))
if not rows:
break # 中断循环
# sql_insert_prod_inst
cur_insert.execute(sql_insert_prod_inst_r)
data = cur_insert.fetchall()
data_insert = str(rows[0][0]), rows[0][2]
rows_insert = [(str(rows[0][0]), str(rows[0][2]))]
if data_insert not in data:
cur_insert.executemany(sql_insert_prod_inst, rows)
# sql_insert_contact_manager_info
cur_insert.executemany(sql_insert_contact_manager_info, rows_insert)
target_db.commit() # 提交
# sql_insert_order_item
cur_insert.execute(sql_insert_order_item_r)
data = cur_insert.fetchall()
data_insert = str(rows[0][0]), str(rows[0][1])
rows_insert = [(str(rows[0][0]), str(rows[0][1]), str(rows[0][2]))]
if data_insert not in data:
cur_insert.executemany(sql_insert_order_item, rows_insert)
target_db.commit() # 提交
# sql_insert_contact_cust_info
cur_insert.execute(sql_insert_contact_cust_info_r)
data = cur_insert.fetchall()
data_insert = str(rows[0][5]), str(rows[0][6])
rows_insert = [(str(rows[0][5]), str(rows[0][6]))]
if data_insert not in data:
cur_insert.executemany(sql_insert_contact_cust_info, rows_insert)
target_db.commit() # 提交
# sql_insert_contact_cust_info
# cur_insert.execute(sql_insert_contact_manager_info_r)
# data = cur_insert.fetchall()
# data_insert = str(rows[0][0]), rows[0][2]
# rows_insert = [(str(rows[0][0]), str(rows[0][2]))]
# if data_insert not in data:
# cur_insert.executemany(sql_insert_contact_manager_info, rows_insert)
# target_db.commit() # 提交
print('开始执行contact_cust_info_update:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
cur_insert.execute('select owner_cust_id,use_cust_id from bossInfo_contact_cust_info ')
data_contact = cur_insert.fetchall()
for owner, use in data_contact:
# owner_cust_name
sql_select_owner_cust_name = "select cust_name,region_id from CUS_CUST.XY_CUSTOMER@to_crm30db " \
" where cust_id = " + owner
# use_cust_name
sql_select_use_cust_name = "select cust_name from CUS_CUST.XY_CUSTOMER@to_crm30db " \
" where cust_id = " + use
# cust_mobile_phone
sql_select_cust_mobile_phone = "select mobile_phone from CUS_CUST.CONTACTS_INFO@to_crm30db where contact_id = (" \
"select contact_id from CUS_CUST.CUST_CONTACT_INFO_REL@to_crm30db " \
" where cust_id =" + owner + ")"
# 收集结果集
cur_select.execute(sql_select_owner_cust_name)
rows_owner_cust_name = cur_select.fetchone()
cur_select.execute(sql_select_use_cust_name)
rows_use_cust_name = cur_select.fetchone()
cur_select.execute(sql_select_cust_mobile_phone)
rows_cust_mobile_phone = cur_select.fetchone()
# 插入空值
rows_cust_mobile_phone_str = rows_cust_mobile_phone[0] if rows_cust_mobile_phone[0] else ""
# 更新 contact_cust_info
sql_update_contact_cust_info = "UPDATE bossInfo_contact_cust_info set owner_cust_name =" + "'" + rows_owner_cust_name[0] +\
"', use_cust_name =" + "'" + rows_use_cust_name[0] + \
"', region_id =" + "'" + str(rows_owner_cust_name[1]) + \
"' , cust_mobile_phone =" + "'" + rows_cust_mobile_phone_str + "'" + \
" where owner_cust_id =" + owner
cur_insert.execute(sql_update_contact_cust_info)
target_db.commit() # 提交
print('开始执行contact_manager_info_update:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
cur_insert.execute('select prod_inst_id,acc_num from bossInfo_contact_manager_info where manager_mobile_phone = "" or manager_mobile_phone is null')
data_contact = cur_insert.fetchall()
for prod, acc in data_contact:
# cust_manage
sql_select_manager = "select attr_value from ord_so.ord_prod_inst_attr@to_crm30db " \
" where prod_inst_id =" + prod + "and attr_id = 4604"
# manage_mobile_phone
sql_select_manage_mobile = "select attr_value from ord_so.ord_prod_inst_attr@to_crm30db " \
" where prod_inst_id =" + prod + "and attr_id = 4605"
# 收集结果集
cur_select.execute(sql_select_manager)
rows_manager = cur_select.fetchone()
cur_select.execute(sql_select_manage_mobile)
rows_manage_mobile = cur_select.fetchone()
# 插入空值
rows_manager_str = rows_manager[0] if rows_manager else ""
rows_manager_mobile_str = rows_manage_mobile[0] if rows_manage_mobile else ""
# 更新 contact_manager_info
sql_update_contact_manager_info = "UPDATE bossInfo_contact_manager_info set cust_manager = " + "'" + rows_manager_str + "'" + \
" where prod_inst_id =" + prod
cur_insert.execute(sql_update_contact_manager_info)
sql_update_contact_manager_info = "UPDATE bossInfo_contact_manager_info set manager_mobile_phone = " + "'" + rows_manager_mobile_str + "'"\
+ " where prod_inst_id =" + prod
cur_insert.execute(sql_update_contact_manager_info)
target_db.commit() # 提交
print('开始执行Order_Item_update:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
cur_insert.execute('select prod_inst_id,order_item_id from bossInfo_order_item where create_date = "" or create_date is null')
data_order = cur_insert.fetchall()
for prod, order in data_order:
sql_select_order = "SELECT cust_order_id, status_cd, service_offer_id, service_offer_name, apply_obj_spec_name, create_staff_name, " \
"create_org_name, update_staff_name, update_org_name,accept_region_id,create_date FROM ORD_SO.ORDER_ITEM @ to_crm30db " \
"where order_item_id =" + order
# 收集结果集
cur_select.execute(sql_select_order)
rows_order = cur_select.fetchone()
for i in range(9):
rows_order[i] if rows_order[i] else ""
# 更新 order_item
sql_update_order_item = "UPDATE bossInfo_order_item set cust_order_id = " + "'" + str(rows_order[0]) +\
"', status_cd =" + "'" + str(rows_order[1]) + \
"', service_offer_id =" + "'" + str(rows_order[2]) + \
"', service_offer_name =" + "'" + str(rows_order[3]) + \
"', apply_obj_spec_name =" + "'" + str(rows_order[4]) + \
"', create_staff_name =" + "'" + str(rows_order[5]) + \
"', create_org_name =" + "'" + str(rows_order[6]) + \
"', update_staff_name =" + "'" + str(rows_order[7]) + \
"', update_org_name =" + "'" + str(rows_order[8]) + \
"', accept_region_id =" + "'" + str(rows_order[9]) + \
"', create_date =" + "'" + str(rows_order[10]) + "'" + \
" where order_item_id =" + order
cur_insert.execute(sql_update_order_item)
target_db.commit() # 提交
# 更新 cust_order_nbr
sql_select_order_nbr = "SELECT cust_order_nbr FROM ORD_SO.CUSTOMER_ORDER @ to_crm30db " \
"where accept_lan_id = '8420600' and cust_order_id =" + str(rows_order[0])
cur_select.execute(sql_select_order_nbr)
rows_order_nbr = cur_select.fetchone()
print(rows_order_nbr)
sql_update_order_nbr = "UPDATE bossInfo_order_item set cust_order_nbr =" + str(rows_order_nbr[0]) + \
" where cust_order_id =" + str(rows_order[0])
cur_insert.execute(sql_update_order_nbr)
target_db.commit() # 提交
print('执行成功:', time.strftime("%Y-%m-%d %H:%M:%S", time.localtime()))
cur_select.close()
cur_insert.close()
source_db.close()
target_db.close()