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ceil(n) ´óÓÚ»òµÈÓÚÊýÖµnµÄ×îСÕûÊý¡¡¡¡select ceil(10.6) from dual; 11
floor(n) СÓÚµÈÓÚÊýÖµnµÄ×î´óÕûÊý¡¡ select ceil(10.6) from dual; 10
mod(m,n) m³ýÒÔnµÄÓàÊý,Èôn=0,Ôò·µ»Øm select mod(7,5) from dual; 2
power(m,n) mµÄn´Î·½¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡ select power(3,2) from dual; 9
round(n,m) ½«nËÄÉáÎåÈë,±£ÁôСÊýµãºómλ¡¡¡¡select round(1234.5678,2) from dual; 1234.57
sign(n) Èôn=0,Ôò·µ»Ø0,·ñÔò,n>0,Ôò·µ»Ø1,n<0,Ôò·µ»Ø-1 select sign(12) from dual; 1
sqrt(n) nµÄƽ·½¸ù¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡select sqrt(25) from dual ; 5
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initcap(char) °Ñÿ¸ö×Ö·û´®µÄµÚÒ»¸ö×Ö·û»»³É´óд¡¡¡¡select initicap('mr.ecop') from dual; Mr.Ecop
lower(char) Õû¸ö×Ö·û´®»»³ÉСд¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡select lower('MR.ecop') from dual; mr.ecop
replace(char,str1,str2) ×Ö·û´®ÖÐËùÓÐstr1»»³Éstr2 select replace('Scott','s','Boy') from dual; Boycott
substr(char,m,n) È¡³ö´Óm×Ö·û¿ªÊ¼µÄn¸ö×Ö·ûµÄ×Ó´®¡¡¡¡select substr('ABCDEF',2,2) from dual; CD
length(char) Çó×Ö·û´®µÄ³¤¶È¡¡¡¡¡¡¡¡select length('ACD') from dual; 3
|| ²¢ÖÃÔËËã·û¡¡¡¡¡¡ select 'ABCD'||'EFGH' from dual; ABCDEFGH
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sysdate µ±Ç°ÈÕÆÚºÍʱ¼ä select sysdate from dual;
last_day ¡¡±¾ÔÂ×îºóÒ»Ìì select last_day(sysdate) from dual;
add_months(d,n)¡¡µ±Ç°ÈÕÆÚdºóÍÆn¸öÔ select add_months(sysdate,2) from dual;
months_between(d,n) ÈÕÆÚdºÍnÏà²îÔÂÊý select months_between(sysdate,to_date('20020812','YYYYMMDD')) from dual;
next_day(d,day) dºóµÚÒ»ÖÜÖ¸¶¨dayµÄÈÕÆÚ select next_day(sysdate,'Monday') from dual;
day ¸ñʽ¡¡¡¡ÓС¡¡¡'Monday' ÐÇÆÚÒ»¡¡¡¡'Tuesday' ÐÇÆÚ¶þ
'wednesday' ¡¡ÐÇÆÚÈý   'Thursday' ÐÇÆÚËÄ    'Friday' ÐÇÆÚÎå
'Saturday' ÐÇÆÚÁù   'Sunday' ÐÇÆÚÈÕ
4¡¢ÌØÊâ¸ñʽµÄÈÕÆÚÐͺ¯Êý
Y»òYY»òYYY ÄêµÄ×îºóһ룬Á½Î»£¬Èýλ select to_char(sysdate,'YYY') from dual;
Q ¼¾¶È,1-3ÔÂΪµÚÒ»¼¾¶È¡¡¡¡¡¡¡¡select to_char(sysdate,'Q') from dual;
MM ¡¡Ô·ÝÊý¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡select to_char(sysdate,'MM') from dual;
RM Ô·ݵÄÂÞÂ