鍙栧緱褰撳墠鏃墮棿鐨勬椂鍒嗙
select to_char(sysdate,'yyyymmdd hh24:mi:ss') from dualselect substr(to_char(sysdate,'yyyymmdd hh24:mi:ss'),10,2 )from dualselect substr(to_char(sysdate,'yyyymmdd hh24:mi:ss'),13,2 )from dualselect substr(to_char(sysdate,'yyyymmdd hh24:mi:ss'),16,2 )from dual鍙互璇曡瘯鐪嬭繖鐜╂剰
涓嶇煡閬撴槸鍚︽湁闂錛?br />
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2.oracle涓棩鏈熸煡璇㈢殑鏃跺?瑕佸姞涓婂崟寮曞彿
3.oracle鏄澶у皬鍐欐晱鎰熺殑where ename='smith'鍜寃here ename='SMITH'鏄笉涓鏍風殑
4.like妯＄硦鏌ヨ%鍙互鍖歸厤浠繪剰闀垮害 _鍙互鍖歸厤涓涓暱搴︾殑鍐呭
5.oracle涓璿archar2鐢ㄦā緋婃煡璇㈢殑鏃跺欎竴涓瓧姣嶅拰涓涓眽瀛?閮芥槸鐢ㄤ竴涓笅鍒掔嚎鏉ュ尮閰嶇殑
6.select upper('smith') from dual
select * from emp where ename = upper('smith')
lower()灝忓啓
initcap()鎶婄涓涓皬鍐欏瓧姣嶅彉鍖栨垚澶у啓
7.select contact('a','b') from dual寤鴻浣跨敤||
8.select substr('hello',1,3)-------------substr鍦╫racle涓粠0鍜?寮濮嬫病鏈夊尯鍒俿elect substr('hello',0,3)
select length('hello')
select replace('hello','l','x')
select substr('hello',-3) from dual------------llo
select substr('hello',-1,3) from dual -------------o
9.oracle涓?---鏃ユ湡-錛?錛夋暟瀛?鏃ユ湡
----鏃ユ湡-鏃ユ湡=鏁板瓧錛堝ぉ鏁幫級
months_between() add_months() next_day() last_day()
10.鈾俿elect empno,ename,to_char(hiredate,'yyyy')year,to_char(hiredate,'mm')month,
to_char(hiredate,'dd')day from emp
to_char()----------鍙互鎷嗗垎
鈾俿elect empno,ename,to_char(hiredate,'yyyy-mm-dd')year from emp
select empno,ename,to_char(hiredate,'fmyyyy-mm-dd')year from emp--鍘繪帀鍓嶅鐨?
鈾倀o_char()鍙互鐢ㄥ湪鏃ユ湡涓婁篃鍙互鐢ㄥ湪鏁板瓧涓?br /> select empno,ename,to_char(sal,'99,999')year from emp
select empno,ename,to_char(sal,'$99,999')year from emp
select empno,ename,to_char(sal,'L99,999')year from emp
11. select ename,nvl(comm,0),(nvl(sal,0)+nvl(comm,0)) from emp
nvl()鍑芥暟鍙互鎶妌ull鐨勫?鍙樻垚 0
12. decode()鍑芥暟
select decode(1,1,'鍐呭1',2,'鍐呭2',3,'鍐呭3') from dual-----鍐呭1
select decode(3,1,'鍐呭1',2,'鍐呭2',3,'鍐呭3') from dual-----鍐呭3
decode鍑芥暟綾諱技if else
************************************************************************************************************
select empno 闆囧憳緙栧彿,ename 闆囧憳濮撳悕,hiredate 闆囦劍鏃ユ湡,
decode(job,'CLERK','涓氬姟鍛?,'SALESMAN','閿鍞漢鍛?,'MANAGER','緇忕悊','ANALYST','鍒嗘瀽','PRESIDENT','鎬昏') 鑱屼綅
from emp
榪欓噷浼氭妸job榪欎釜瀛楁閲屽搴旂殑鐩稿簲鐨勭被浼肩敤ifelse杞崲涓轟綘鎯寵鐨勭粨鏋?br /> ************************************************************************************************************
13.涓嶈兘鐢ㄥ埆鍚嶆潵浣滀負where鏉′歡鐨剆elect ename from emp where ename = 'SMITH'---RIGHT
select ename e from emp where e = 'SMITH'--WRONG
14. select ename,
trunc(months_between(sysdate,hiredate)/12)year,
trunc(mod(months_between(sysdate,hiredate),12)) month,
trunc(mod(sysdate-hiredate,30))day
from emp
榪欎釜璁＄畻浜?鍒板綋鍓嶆椂闂翠負姝?鏌愪釜浜哄伐浣滄椂闂?澶ф
15. 鏌ュ嚭闆囧憳琛ㄤ腑闆囧憳鐨勫悕瀛椾互鍙婇瀵肩殑鍚嶅瓧
---->select e.ename 闆囧憳鍚嶅瓧,p.ename 鍙︿竴涓泧鍛樺悕瀛?br /> from emp e,emp p
榪欓噷鍋氬嚭絎涘崱灝旂Н,鑷繁鍋氫竴涓?鐪嬩笅鏁堟灉灝變細鍗沖埢鏄庣櫧.涓嶈鍘繪兂涓轟粈涔堣繖鏍?
---->榪囨護
select e.ename 闆囧憳鍚嶅瓧,p.ename 鍙︿竴涓泧鍛樺悕瀛?br /> from emp e,emp p
where e.mgr = p.empno
16. 鏌ヨ闄ゆ瘡涓泧鍛樼殑濮撳悕錛屽伐璧勶紝閮ㄩ棬鍚嶇О錛屽伐璧勫湪鍏徃鐨勭瓑綰?鍙婂叾棰嗗鐨勫鍚嶄互鍙婂伐璧勬墍鍦ㄥ叕鍙哥殑絳夌駭
----->鍏堟煡鍑烘潵姣忎釜闆囧憳鐨勫鍚嶏紝宸ヨ祫錛岄儴闂ㄥ悕縐幫紝宸ヨ祫鍦ㄥ叕鍙哥殑絳夌駭
select e.ename 闆囧憳鍚嶇О,e.sal 闆囧憳钖按,d.dname 閮ㄩ棬鍚嶇О,s.grade 宸ヨ祫絳夌駭
from emp e,salgrade s,dept d
where e.sal between losal and hisal and e.deptno = d.deptno
----->鍐嶆煡 姣忎釜闆囧憳鐨?棰嗗鍚嶅瓧
select e.ename 闆囧憳鍚嶇О,e.sal 闆囧憳钖按,
d.dname 閮ㄩ棬鍚嶇О,s.grade 宸ヨ祫絳夌駭,
p.ename 闆囧憳棰嗗
from emp e,salgrade s,dept d,emp p
where e.sal between losal and hisal
and e.deptno = d.deptno
and e.mgr = p.empno
---->鍐嶆煡 姣忎釜棰嗗鐨勫伐璧勭瓑綰?br />
select e.ename 闆囧憳鍚嶇О,e.sal 闆囧憳钖按,
d.dname 閮ㄩ棬鍚嶇О,s.grade 宸ヨ祫絳夌駭,
p.ename 闆囧憳棰嗗,ls.grade 棰嗗宸ヨ祫絳夌駭
from emp e,salgrade s,dept d,emp p,salgrade ls
where e.sal between s.losal and s.hisal
and e.deptno = d.deptno
and e.mgr = p.empno
and p.sal between ls.losal and ls.hisal
---->浼樺寲
select e.ename 闆囧憳鍚嶇О,e.sal 闆囧憳钖按,
d.dname 閮ㄩ棬鍚嶇О,
decode(s.grade,1,'絎簲絳夌駭',2,'絎洓絳夌駭',3,'絎笁絳夌駭',4,'絎簩絳夌駭',5,'絎竴絳夌駭') 宸ヨ祫絳夌駭,
p.ename 闆囧憳棰嗗,
decode(ls.grade,1,'絎簲絳夌駭',2,'絎洓絳夌駭',3,'絎笁絳夌駭',4,'絎簩絳夌駭',5,'絎竴絳夌駭') 棰嗗宸ヨ祫絳夌駭
from emp e,salgrade s,dept d,emp p,salgrade ls
where e.sal between s.losal and s.hisal
and e.deptno = d.deptno
and e.mgr = p.empno
and p.sal between ls.losal and ls.hisal
17. 宸﹀彸閾炬帴
宸﹁繛鎺ヨ〃紺?宸﹁竟琛ㄤ腑鎵鏈夌殑瀛楁閮戒細鍒楀嚭鏉?浣嗘槸鍙寵竟娌℃湁鐨勪互絀烘樉紺?br />
鍙寵繛鎺ヨ〃紺?鍙寵竟琛ㄤ腑鎵鏈夌殑瀛楁閮戒細鍒楀嚭鏉?浣嗘槸宸﹁竟娌℃湁鐨勪互絀烘樉紺?br />
18. sql1999璇硶
19. 緇勫嚱鏁?br />
count(),max(),min(),avg(),sum()
鍒嗙粍緇熻------------->
group by 鍜?having 鍙互榪炵敤鐨?br />
select e.deptno,d.dname,avg(e.sal)
from emp e,dept d
where e.deptno = d.deptno
group by e.deptno,d.dname having avg(e.sal)>2000
20. 鏄劇ず鍑洪潪閿鍞漢鍛樺伐浣滃悕縐頒互鍙婁粠浜嬪悓涓宸ヤ綔闆囧憳鐨勬湀宸ヨ祫鐨勬誨拰銆傚茍涓旇婊¤凍
浠庝簨鍚屼竴宸ヤ綔鐨勯泧鍛樼殑鏈堝伐璧勫悎璁″ぇ浜?000錛岃緭鍑虹粨鏋滄寜鏈堝伐璧勭殑鍚堣緇熻
---->鍏堟樉紺哄叏閮ㄧ殑闈為攢鍞漢鍛?br />
select ename,job from emp where job<>'SALESMAN'
---->鎸夊伐浣滃垎緇?鍚屾椂姹傚嚭宸ヨ祫鐨勬誨拰
select job,sum(sal) from emp where job<>'SALESMAN' group by job
---->鏈堝伐璧?gt;5000
select job,sum(sal) from emp where job<>'SALESMAN' group by job having sum(sal)>5000
---->鎺掑簭
select job,sum(sal) s from emp where job<>'SALESMAN' group by job having sum(sal)>5000 order by s
21. 姹傚嚭騫沖潎宸ヨ祫鏈楂樼殑閮ㄩ棬
select deptno,max(avg(sal)) from emp group by deptno-------閿欒
select max(avg(sal)) from emp group by deptno-----姝ｇ‘
22. 瀛愭煡璇?br />
---->鏌ヨ姣?654宸ヨ祫楂樼殑闆囧憳淇℃伅
select * from emp where sal > (select sal from emp where empno=7654)
---->鏌ヨ姣?654宸ヨ祫楂樼殑闆囧憳淇℃伅,涓?788浠庝簨鐩稿悓宸ヤ綔鐨勫叏閮ㄩ泧鍛樹俊鎭?br />
-->鍏堟煡璇?654鐨勫伐璧剆elect sal from emp where empno = 7654
-->鍐嶆煡璇?鍚屾椂7788宸ヤ綔select job from emp where empno = 7788
-->緇煎悎select * from emp where sal > (select sal from emp where empno = 7654)
and job = (select job from emp where empno = 7788)
---->鏌ヨ宸ヨ祫鏈浣庣殑闆囧憳鐨勫鍚?宸ヤ綔宸ヨ祫
-->鍏堟煡鍑烘渶浣庡伐璧剆elect min(sal) from emp
-->select ename,job,sal from emp where sal = (select min(sal) from emp)
---->鏌ヨ閮ㄩ棬鍚嶇О錛岄儴闂ㄧ殑鍛樺伐鏁幫紝閮ㄩ棬鐨勫鉤鍧囧伐璧勶紝閮ㄩ棬鐨勬渶浣庢敹鍏ラ泧鍛樼殑濮撳悕(榪欎釜璇彞鍙槸閫傚悎涓涓渶浣庡伐璧勪笉涓鏍風殑)
select e.deptno,count(sal),avg(sal),d.dname from emp e ,dept d where e.deptno = d.deptno
group by e.deptno,d.dname
-->select deptno,count(sal) c,avg(sal) from emp group by deptno
-->select d.dname,ed.c,ed.a from dept d,(select deptno,count(sal) c,avg(sal) a from emp group by deptno) ed where d.deptno = ed.deptno
-->select d.dname,ed.c,ed.a ,ed.min,e.ename from
dept d,
(select deptno,count(sal) c,avg(sal) a,min(sal) min from emp group by deptno) ed ,
emp e
where d.deptno = ed.deptno
and e.sal = ed.min
23. 瀛愭煡璇腑鐨処N
->鏌ヨ姣忎釜閮ㄩ棬鐨勬渶浣庡伐璧勭殑闆囧憳淇℃伅
---->select * from emp where sal in(select min(sal) from emp group by deptno)
24. create table myemp as select * from emp
榪欎釜璇彞淇濆瓨浜唀mp琛ㄧ殑鍘熷淇℃伅浼氬皢琛ㄧ粨鏋勫拰鏁版嵁瀹屾暣鐨勫鍒跺嚭鏉?br />
榪欎釜鎿嶄綔涓嶄細鎶婄害鏉熷甫榪涙潵鐨勩?/font>
to_date('String','yyyy-mm-dd')
create table myemp as select * from emp where empno=10琛ㄧず鍙槸鍖呭惈10閮ㄩ棬闆囧憳鐨勪竴寮犱復鏃惰〃
25. 鍦╫racle涓瘡涓涓摼鎺ュ埌鏁版嵁搴撶殑紿楀彛錛岄兘浼氬緩绔嬩笌鏁版嵁搴撶殑涓涓猻ession
涓涓猻ession濡傛灉鏇存柊浜嗘暟鎹簱涓殑璁板綍錛屽叾浠杝ession鏄棤娉曟洿鏂扮殑瑕佺瓑寰呭鏂規彁浜や箣鍚庢墠鍏佽鏇存柊銆備竴縐嶆閿佺殑姒傚康
select * from tab;
select * from tab where tname = '';
26. select * from (select rownum rn,ename,job,sal,hiredate from emp where rownum<=10) e where e.rn>5鍒嗛〉
27. a.鍒涘緩鐢ㄦ埛:create user test identified by test(瑕佸垱寤虹敤鎴峰繀欏諱嬌鐢ㄧ鐞嗗憳鐢ㄦ埛sys)
娌℃湁session鐨勬潈闄愭棤娉曠櫥闄嗙殑ora-01045,瑙ｅ喅鍔炴硶鎺堟潈grant
grant create session to test--->灝嗗垱寤簊ession鐨勬潈闄愮粰test鐢ㄦ埛
****************************************榪欎釜鏃跺欎嬌鐢╰est鐢ㄦ埛鐧婚檰鎴愬姛鐨勮瘽錛岃〃紺哄垱寤轟簡涓涓猻ession
b.涓涓柊鐨勭敤鎴鋒墍鏈夌殑鏉冮檺閮借鍒嗗埆璧嬩簣錛屼竴涓鑹插寘鍚緢澶氭潈闄?br />
c.Oracle涓璫onnect錛宺esource
grant connect,resource to test--->榪欎釜鏃跺?鍙互寤鴻〃浜?br />
d.瓚呯駭綆＄悊鍛樺彲浠ヤ慨鏀規櫘閫氱鐞嗗憳瀵嗙爜alter user 鐢ㄦ埛鍚?identified by 瀵嗙爜
e.alter user 鐢ㄦ埛鍚?pasword expire 璁╃敤鎴風涓嬈″瘑鐮佸け鏁?寮哄埗淇敼
f.alter user 鐢ㄦ埛鍚?account lock 灝嗙敤鎴烽攣浣?br />
g.alter user 鐢ㄦ埛鍚?account unlock 瑙ｉ攣鐢ㄦ埛
28. 鎯寵闂叾浠栫敤鎴風殑琛紝闇瑕佹巿浜堝叾浠栫敤鎴瘋〃鐨勬潈闄?br />
grant SELECT ,DELETE on scott.emp to test---灝唖cott.emp鏌ヨ鍜屽垹闄ょ殑鏉冮檺緇檛est鐢ㄦ埛
鍥炴敹鏉冮檺
revoke 鏉冮檺 on 鐢ㄦ埛.琛ㄦ槑 from 鐢ㄦ埛
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