oracle nvl decode
SELECT
DECODE(ÁÐ,0,'Q'1,'P',2,'O')¡¡AS ret
from dual
--·ÖÎö: µ± ÁÐ=0ʱ,½«"Q"¸³Öµ
--µ± ÁÐ =1ʱ,½«"P"¸³Öµ
--µ± ÁÐ=2ʱ,½«"O"¸³Öµ
--NVL()º¯Êý:
--NVL(ARG,VALUE)´ï±êÈç¹ûÇ°ÃæµÄARGֵΪNULLÄÇô·µ»ØµÄֵΪºóÃæµÄVALUE¶þÕß½áºÏʹÓÃ:
DECODE(NVL(±äÁ¿ ''),'','-','OK')
//·ÖÎö:
--Èô ±äÁ¿ ÊÇ·ñΪ¿Õ.ÈôΪ¿Õ¸³¸ø¿ÕÖµ[NVLº¯Êý]
--Æä´Î,ÅжÏÈ¡³öµÄ×Ö¶ÎÊÇ·ñΪ¿Õ,Èç¹ûÊÇÔò¸³¸ø'-'
--ĬÈÏ´¦ÀíÊÇOK¡£
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Example:
create table courses(
cid varchar(20) not null primary key,
cname varchar(20) not null,
ctype integer,
ctime date DEFAULT SYSDATE,
cscore float not null
)
insert into courses values('ss01','.NET',0,TO_DATE('2009-8-28','yyyy-mm-dd'),94)
insert into course ......
ÈçºÎͨ¹ýSqlplus´´½¨Ò»¸öoracleµÄuser
1£¬Í¨¹ýsystem¹ÜÀíÔ±Á¬½Óµ½ÒªÌí¼ÓUSERµÄDB
»òÕßͨ¹ýÒÔÏÂÃüÁ Connect system/manager@user_datebase AS SYSDBA ;ÒÔSYSµÇ½ȥ´´½¨Óû§
2,´´½¨Óû§²¢·ÖÅäȨÏÞ
drop user asset cascade; ɾ³ ......
Ò»°ãµÄ¹«Ë¾Í¨³£»áÔÚËûÃǵÄÐÅϢϵͳ¼Ü¹¹ÖÐÒýÈë¶àÖÖÊý¾Ý¿âƽ̨£¬Í¬Ê±ÒýÈëÈýµ½ËÄÖÖ²»Í¬µÄRDBMS½â¾ö·½°¸µÄÖдóÐ͹«Ë¾Ò²²¢²»ÉÙ¼û£¬µ±È»ÕâЩ¹«Ë¾ÀïÃæµÄDBAÃÇͨ³£Ò²ÐèҪͬʱӵÓйÜÀí¶àÖÖ²»Í¬Æ½Ì¨µÄ¼¼ÄÜÁË¡£
Ö»ÔÚÒ»ÖÖÆ½Ì¨ÉÏÕ¹¿ª¹¤×÷µÄÊý¾Ý¿âר¼ÒÃÇҲͨ³£»áÆÚ´ý×ÅÔÚËûÃǵÄÏÂÒ»·Ý¹¤×÷ÖÐÄÜѧµ½µã²»Ò»ÑùµÄ¶«Î÷£¬ÄÇЩÓÐÓÂÆøµÄÈËÃÇÔòÔ¸Òâ ......
ÎÒµÄmyeclipseÊÇ6.5°æ, oracleÊÇ10.2.0.1µÄÖÐÎİæ.
myeclipseÆô¶¯ÊÇÓ¢ÎĵÄ,DB BrowserËÀ»îÁ¬²»ÉÏoracle,±¨Á½¸ö´íÎó(¾ßÌå²»¼ÇµÃÁË).ºóÀ´¿´ÁËÈçÏÂÎÄÕ£¬ÖªµÀÁËÔÒò¡£
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Hi,
a ......
select trunc(sysdate ,'yyyy') from dual --±¾Äê¶ÈµÚÒ»Ìì
select trunc(sysdate ,'mm') from dual --±¾ÔµÚÒ»Ìì
&nbs ......