python3:使用cx_Oracle 操作Oracle数据库
1,安装 cx_Oracle 注意版本号 要和python版本一致
pip install cx_Oracle
2安装 Oracle Instant Client
会报 DPI-1047: 64-bit Oracle Client library cannot be load
下载地址 (注意版本)
https://www.oracle.com/database/technologies/instant-client/downloads.html
解压之后将安装文件里的.dll文件 全部复制到python安装目录 和python.exe 一级
如果没有做这一步 会报 cx_Oracle.DatabaseError: DPI-1072: the Oracle Client library version is unsupported
有的文章说 设置环境变量 我试了 没用 然后删了 最后直接将.dll全部拷贝到python目录,然后成功了 具体为什么 我也不知道…
3,测试程序
import cx_Oracle
import os
import csv
from log.mylog import getMyLogger
log = getMyLogger(__name__)
# 中文乱码处理
os.environ['NLS_LANG'] = 'SIMPLIFIED CHINESE_CHINA.ZHS16GBK'
if __name__ == '__main__':
# 数据库连接对象
conn = cx_Oracle.connect('用户名/密码@ip地址:端口号/ora11g')
# 数据库执行对象
curs = conn.cursor()
# sql语句
sql = 'select * from XXXXX '
# sql执行结果
result = curs.execute(sql)
# 获取表的列名
colsname = curs.description
title = [i[0] for i in colsname]
print(title)
i = 1
for item in result:
log.info('%s %s', i, item)
i = i + 1
# 将数据写入CSV文件 网上抄的 我没成功
try:
with open("table_name.csv", 'w') as csvfile:
writer = csv.writer(csvfile)
writer.writerow(title)
writer.writerows(result)
except Exception as a:
print("文件写入数据错误", a)
curs.close()
conn.close()
勉强可以有点实际应用的的:
import cx_Oracle
import os
import openpyxl
from openpyxl import Workbook
from log.mylog import getMyLogger
log = getMyLogger(__name__)
# 中文乱码处理
os.environ['NLS_LANG'] = 'SIMPLIFIED CHINESE_CHINA.ZHS16GBK'
class OracleOper(object):
def __init__(self, url='用户名/密码@ip地址:端口号/ora11g'):
self.__conn = cx_Oracle.connect(url)
self.curs = self.__conn.cursor()
def execute_sql(self, exe_sql='select 1 from dual'):
execute_result = self.curs.execute(exe_sql)
title = [t[0] for t in self.curs.description]
result_list = [tuple(title)]
i = 0
for item in execute_result:
result_list.append(item)
i = i + 1
self.__close()
print('查询总数', len(result_list) - 1)
return result_list
def __close(self):
self.curs.close()
self.__conn.close()
def add_excel(data_tuple, file_name='新建表格', sheet_name='sheet1'):
path = os.getcwd() # 获取当前路径
file_path = path + '\\' + file_name + '.xlsx'
if not os.path.exists(file_path):
wb = Workbook()
wb.save(file_path)
wb = openpyxl.load_workbook(file_path)
wb.create_sheet(title=sheet_name, index=0)
table = wb.worksheets[0]
nrows = 1
for tupite in data_tuple:
ncolumns = 0
for item in tupite:
ncolumns = ncolumns + 1
table.cell(nrows, ncolumns, item) # 行，列，值 这里是从1开始计数的
nrows = nrows + 1
wb.save(file_path) # 一定要保存
print(file_name + '已保存')
if __name__ == '__main__':
# 预发
# pre_url = '用户名/密码@ip地址:端口号/ora11g'
oracle_oper = OracleOper()
sql_str = '''
select aaa from dual
'''
result_list = oracle_oper.execute_sql(sql_str)
add_excel(result_list, '文件名', 'sheet名')
大数据量有时会出现一个bug
error
Traceback (most recent call last):
File "D:/Work/Data/OracleData/OracleServer/oracleServer.py", line 99, in <module>
add_excel(result_list, '1111', sheet_name)
File "D:/Work/Data/OracleData/OracleServer/oracleServer.py", line 53, in add_excel
table.cell(nrows, ncolumns, item) # 行，列，值 这里是从1开始计数的
File "C:\Software\Python\lib\site-packages\openpyxl\worksheet\worksheet.py", line 240, in cell
cell.value = value
File "C:\Software\Python\lib\site-packages\openpyxl\cell\cell.py", line 219, in value
self._bind_value(value)
File "C:\Software\Python\lib\site-packages\openpyxl\cell\cell.py", line 195, in _bind_value
value = self.check_string(value)
File "C:\Software\Python\lib\site-packages\openpyxl\cell\cell.py", line 162, in check_string
raise IllegalCharacterError
openpyxl.utils.exceptions.IllegalCharacterError
使用pandas 写入更快
#将数据库查询到的数据塞入
execute_result = curs.execute(exe_sql)
title = [t[0] for t in self.curs.description]
df = pd.DataFrame(execute_result, columns=title)
写入到excel
df1.to_excel(‘excel_name.xlsx’, sheet_name=‘sheet1’, engine=‘xlsxwriter’)
# 写入csv
df.to_csv(‘csv_name.csv’)
# 写入html
df.to_html(‘csv_name.html’)