oracle sql日期比较和查看表空间大小

在今天之前:

select * from up_date where update < to_date('2007-09-07 00:00:00','yyyy-mm-dd hh24:mi:ss')

select * from up_date where update <= to_date('2007-09-07 00:00:00','yyyy-mm-dd hh24:mi:ss')

在今天只后:

select * from up_date where update > to_date('2007-09-07 00:00:00','yyyy-mm-dd hh24:mi:ss')

select * from up_date where update >= to_date('2007-09-07 00:00:00','yyyy-mm-dd hh24:mi:ss')

精确时间:

select * from up_date where update = to_date('2007-09-07 00:00:00','yyyy-mm-dd hh24:mi:ss')

在某段时间内:

select * from up_date where update between to_date('2007-07-07 00:00:00','yyyy-mm-dd hh24:mi:ss') and to_date('2007-09-07 00:00:00','yyyy-mm-dd hh24:mi:ss')

select * from up_date where update < to_date('2007-09-07 00:00:00','yyyy-mm-dd hh24:mi:ss') and update > to_date('2007-07-07 00:00:00','yyyy-mm-dd hh24:mi:ss')

select * from up_date where update <= to_date('2007-09-07 00:00:00','yyyy-mm-dd hh24:mi:ss') and update >= to_date('2007-07-07 00:00:00','yyyy-mm-dd hh24:mi:ss')
查看表大小：

select segment_name,bytes/1024/1024 from user_segments;

select segment_name,bytes/1024/1024 from dba_segments;