[python2]local variable referenced before assignment问题

问题描述

class Test(obj):

def __init__(self): pass def _is_flag(self): try:v_sql='''Select count(*) From tablename'''push_ctrl_conn=oracle(’ETL_TEST’)self.reach_flag=push_ctrl_conn.runsql(v_sql,1)[0][0] except Exception,e:self._set_scan_state(’22’, str(e)) finally:push_ctrl_conn.close()def run(self): self._is_flag()

if name == ’__main__’:

test_case=Test()test_case.run()

类似这种格式,然后就报了UnboundLocalError: local variable ’push_ctrl_conn’ referenced before assignment

问题解答

try语法块不一定执行，即push_ctrl_conn不一定被赋值。很常见的错误，一般可以在try语法前先赋值。

像这种连接的需求，一般用上下文管理器功能，我猜测oracle库的实例也是支持的。