今天我反对一种新的查询优化问题。SELECT * LEFT JOIN sanrum ON sanrum.sanrum___rforefide = sanrss.sanrss___rforefide AND sanrum.sanrum___rfovsnide = sanrss.sanrss___rfovsnide AND sanrum.sanrum___sanrsside = sanrss.sanrsside
LEFT JOIN sanact ON sanact.sanact___rforefide = sanrum.sanrum___rf
在Python中,import似乎是真正的词汇作用域。这是真的吗?example.py", line 4, in <module>NameError: name 'sys' is not defined
在Perl中,use语句不是词汇作用域,但是如果您试图从词汇(即在子例程中)定义它们,Perl不会给出语法错误。在Python中,这似乎不是事情的工作方式。在import__s中,在词汇上定义有什