py读取Oracle数据库数据方法

# -----------------封装读取Oracle数据库数据-----------------
# coding:utf-8
import cx_Oracle
import os

os.environ['NLS_LANG'] = 'SIMPLIFIED CHINESE_CHINA.UTF8'
print("cx_Oracle版本：", cx_Oracle.clientversion())

u'''Oracle数据库相关操作
连接数据库名称如：xxx
查询数据：oracle_getrows
查询某个字段对应的字符串：oracle_getstring
执行sql语句：oracle_sql
关闭oracle连接：oracle_close
'''
dbname = {"user": "wapn_czth",
          "pwd": "123456",
          "dsn": "127.0.0.1:1521/ORCL"}

class OracleUtil():
    def __init__(self):
        ''' 连接池方式'''
        self.db_info = dbname
        self.conn = OracleUtil.__getConnect(self.db_info)

    @staticmethod
    def __getConnect(db_info):
        ''' 静态方法，从连接池中取出连接'''
        try:
            con = cx_Oracle.connect(db_info['user'], db_info['pwd'], db_info['dsn'])
            return con
        except Exception as a:
            print("数据库连接异常：%s"%a)

    def oracle_getrows(self, sql):
        ''' 执行查询sql'''
        try:
            cursor = self.conn.cursor()
            try:
                cursor.execute(sql)
                rows = cursor.fetchall()
                return rows
            except Exception as a:
                print("执行sql出现异常：%s"%a)
            finally:
                cursor.close()
        except Exception as a:
            print("数据库连接异常：%s"%a)

    def oracle_getstring(self, sql):
        ''' 查询某个字段的对应值'''
        rows = self.oracle_getrows(sql)
        if rows != None:
            for row in rows:
                for i in row:
                 return i

    def oracle_sql(self, sql):
        ''' 执行sql语句'''
        try:
            cursor = self.conn.cursor()
            try:
                cursor.execute(sql)
            except Exception as a:
                print("执行sql出现异常：%s" % a)
            finally:
                cursor.close()
        except Exception as a:
                print("数据库连接异常：%s" % a)


    def orcle_close(self):
            ''' 关闭orcle连接'''

            try:
                self.conn.close()
            except Exception as a:
                print("数据库关闭时异常：%s"%a)

if __name__ == "__main__":
        oracl = OracleUtil()
        sql = "select t.union_id  from th_user_info t where t.union_id is not null"
        s = oracl.oracle_getrows(sql)
        print(type(s))
        for j in s:
            for i in j:
                r = print("union_id:", i)

        oracl.orcle_close()