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--»ñÈ¡Á½Ê±¼äµÄÏà²îºÀÃëÊý
select ceil((To_date('2008-05-02 00:00:00' , 'yyyy-mm-dd hh24-mi-ss') - To_date('2008-04-30 23:59:59' , 'yyyy-mm-dd hh24-mi-ss')) * 24 * 60 * 60 * 1000) Ïà²îºÀÃëÊý from DUAL;
/*
Ïà²îºÀÃëÊý
----------
86401000
1 row selected
*/
--»ñÈ¡Á½Ê±¼äµÄÏà²îÃëÊý
select ceil((To_date('2008-05-02 00:00:00' , 'yyyy-mm-dd hh24-mi-ss') - To_date('2008-04-30 23:59:59' , 'yyyy-mm-dd hh24-mi-ss')) * 24 * 60 * 60) Ïà²îÃëÊý from DUAL;
/*
Ïà²îÃëÊý
----------
86401
1 row selected
*/
--»ñÈ¡Á½Ê±¼äµÄÏà²î·ÖÖÓÊý
select ceil(((To_date('2008-05-02 00:00:00' , 'yyyy-mm-dd hh24-mi-ss') - To_date('2008-04-30 23:59:59' , 'yyyy-mm-dd hh24-mi-ss'))) * 24 * 60) Ïà²î·ÖÖÓÊý from DUAL;
/*
Ïà²î·ÖÖÓÊý
----------
1441
1 row selected
*/
--»ñÈ¡Á½Ê±¼äµÄÏà²îСʱÊý
select ceil((To_date('2008-05-02 00:00:00' , 'yyyy-mm-dd hh24-mi-ss') - To_date('2008-04-30 23:59:59' , 'yyyy-mm-dd hh24-mi-ss')) * 24) Ïà²îСʱÊý from DUAL;
/*
Ïà²îСʱÊý
----------
25
1 row selected
*/
--»ñÈ¡Á½Ê±¼äµÄÏà²îÌìÊý
select ceil((To_date('2008-05-02 00:00:00' , 'yyyy-mm-dd hh24-mi-ss') - To_date('2008-04-30 23:59:59' , 'yyyy-mm-dd hh24-mi-ss'))) Ïà²îÌìÊý from DUAL;
/*
Ïà²îÌìÊý
----------
2
1 row selected
*/
--»ñÈ¡Á½Ê±¼äÔ·ݲî
select (EXTRACT(year from to_date('2009-05-01','yyyy-mm-dd')) - EXTRACT(year from to_date('2008-04-30','yyyy-mm-dd'))) * 12 +
EXTRACT(month from to_date('2008-05-01','yyyy-mm-dd')) - EXTRACT(month from to_date('2008-04-30','yyyy-mm-dd')) months
from dual;
/*
MONTHS
----------
13
1 row selected
*/
--»ñÈ¡Á½Ê±¼äÄê·Ý²î
select EXTRACT(year from to_date('2009-05-01','yyyy-mm-dd')) - EXTRACT(year from to_date('2008-04-30','yyyy-mm-dd')) years from dual;
/*
YEARS
----------
1
1 row select
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