PHP日付処理、mysql日付、時間別照会

date_default_timezone_set('PRC'); //    
echo "  :",date("Y-m-d",time()),"<br>";
echo "  :",date("Y-m-d",strtotime("18 june 2008")),"<br>";
echo "  :",date("Y-m-d",strtotime("-1 day")), "<br>";
echo "  :",date("Y-m-d",strtotime("+1 day")), "<br>";
echo "   :",date("Y-m-d",strtotime("+1 week")), "<br>";
echo "           :",date("Y-m-d G:H:s",strtotime("+1 week 2 days 4 hours 2 seconds")), "<br>";
echo "     :",date("Y-m-d",strtotime("next Thursday")), "<br>";
echo "    :".date("Y-m-d",strtotime("last Monday"))."<br>";
echo "    :".date("Y-m-d",strtotime("last month"))."<br>";
echo "    :".date("Y-m-d",strtotime("+1 month"))."<br>";
echo "   :".date("Y-m-d",strtotime("+10 year"))."<br>";

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#mysql    、  、7 、 30 、  、      
#  
select * from    where to_days(     ) = to_days(now());
#  
SELECT * FROM    WHERE TO_DAYS( NOW( ) ) – TO_DAYS(      ) <= 1
#7 
SELECT * FROM    where DATE_SUB(CURDATE(), INTERVAL 7 DAY) <= date(     )
# 30 
SELECT * FROM    where DATE_SUB(CURDATE(), INTERVAL 30 DAY) <= date(     )
#  
SELECT * FROM    WHERE DATE_FORMAT(      , ‘%Y%m’ ) = DATE_FORMAT( CURDATE( ) , ‘%Y%m’ )
#   
SELECT * FROM    WHERE PERIOD_DIFF( date_format( now( ) , ‘%Y%m’ ) , date_format(      , ‘%Y%m’ ) ) =1