琛ㄧ粨鏋勶細琛?fso_sdept錛?瀛楁 dept_id錛堥儴闂↖D錛夈乨ept_name錛堥儴闂ㄥ悕縐幫級銆乨ept_p_id錛堢埗閮ㄩ棬ID錛?
鍖呭惈鐖墮儴闂ㄥ拰瀛愰儴闂?br />select dept_id,dept_name from fso_sdept where dept_stat=1
start with dept_id=1129 connect by prior dept_id=dept_p_id
涓嶅寘鍚埗閮ㄩ棬鍙寘鍚瓙閮ㄩ棬
select dept_id,dept_name from fso_sdept where dept_stat=1
start with dept_p_id=1129聽 connect by prior dept_id=dept_p_id
]]>
聽
聽
SQL涓殑鍗曡褰曞嚱鏁?
1.ASCII
榪斿洖涓庢寚瀹氱殑瀛楃瀵瑰簲鐨勫崄榪涘埗鏁?
SQL> select ascii(鈥橝鈥? A,ascii(鈥檃鈥? a,ascii(鈥?鈥? zero,ascii(鈥?鈥? space from dual;
A A ZERO SPACE
--------- --------- --------- ---------
65 97 48 32
2.CHR
緇欏嚭鏁存暟,榪斿洖瀵瑰簲鐨勫瓧絎?
SQL> select chr(54740) zhao,chr(65) chr65 from dual;
ZH C
-- -
璧?A
3.CONCAT
榪炴帴涓や釜瀛楃涓?
SQL> select concat(鈥?10-鈥?鈥?8888888鈥?||鈥欒漿23鈥?楂樹咕绔炵數璇?from dual;
楂樹咕绔炵數璇?
----------------
010-88888888杞?3
4.INITCAP
榪斿洖瀛楃涓插茍灝嗗瓧絎︿覆鐨勭涓涓瓧姣嶅彉涓哄ぇ鍐?
SQL> select initcap(鈥檚mith鈥? upp from dual;
UPP
-----
Smith
5.INSTR(C1,C2,I,J)
鍦ㄤ竴涓瓧絎︿覆涓悳绱㈡寚瀹氱殑瀛楃,榪斿洖鍙戠幇鎸囧畾鐨勫瓧絎︾殑浣嶇疆;
C1 琚悳绱㈢殑瀛楃涓?
C2 甯屾湜鎼滅儲鐨勫瓧絎︿覆
I 鎼滅儲鐨勫紑濮嬩綅緗?榛樿涓?
J 鍑虹幇鐨勪綅緗?榛樿涓?
SQL> select instr(鈥檕racle traning鈥?鈥檙a鈥?1,2) instring from dual;
INSTRING
---------
9
6.LENGTH
榪斿洖瀛楃涓茬殑闀垮害;
SQL> select name,length(name),addr,length(addr),sal,length(to_char(sal)) from gao.nchar_tst;
NAME LENGTH(NAME) ADDR LENGTH(ADDR) SAL LENGTH(TO_CHAR(SAL))
------ ------------ ---------------- ------------ --------- --------------------
楂樹咕绔?3 鍖椾含甯傛搗閿尯 6 9999.99 7
7.LOWER
榪斿洖瀛楃涓?騫跺皢鎵鏈夌殑瀛楃灝忓啓
SQL> select lower(鈥橝aBbCcDd鈥?AaBbCcDd from dual;
AABBCCDD
--------
aabbccdd
8.UPPER
榪斿洖瀛楃涓?騫跺皢鎵鏈夌殑瀛楃澶у啓
SQL> select upper(鈥橝aBbCcDd鈥? upper from dual;
UPPER
--------
AABBCCDD
9.RPAD鍜孡PAD(綺樿創瀛楃)
RPAD 鍦ㄥ垪鐨勫彸杈圭矘璐村瓧絎?
LPAD 鍦ㄥ垪鐨勫乏杈圭矘璐村瓧絎?
SQL> select lpad(rpad(鈥檊ao鈥?10,鈥?鈥?,17,鈥?鈥?from dual;
LPAD(RPAD(鈥橤AO鈥?1
-----------------
*******gao*******
涓嶅瀛楃鍒欑敤*鏉ュ～婊?
10.LTRIM鍜孯TRIM
LTRIM 鍒犻櫎宸﹁竟鍑虹幇鐨勫瓧絎︿覆
RTRIM 鍒犻櫎鍙寵竟鍑虹幇鐨勫瓧絎︿覆
SQL> select ltrim(rtrim(鈥?gao qian jing 鈥?鈥?鈥?,鈥?鈥? from dual;
LTRIM(RTRIM(鈥?
-------------
gao qian jing
11.SUBSTR(string,start,count)
鍙栧瓙瀛楃涓?浠巗tart寮濮?鍙朿ount涓?
SQL> select substr(鈥?3088888888鈥?3,8) from dual;
SUBSTR(鈥?
--------
08888888
12.REPLACE(鈥檚tring鈥?鈥檚1鈥?鈥檚2鈥?
string 甯屾湜琚浛鎹㈢殑瀛楃鎴栧彉閲?
s1 琚浛鎹㈢殑瀛楃涓?
s2 瑕佹浛鎹㈢殑瀛楃涓?
SQL> select replace(鈥檋e love you鈥?鈥檋e鈥?鈥檌鈥? from dual;
REPLACE(鈥橦
----------
i love you
13.SOUNDEX
榪斿洖涓涓笌緇欏畾鐨勫瓧絎︿覆璇婚煶鐩稿悓鐨勫瓧絎︿覆
SQL> create table table1(xm varchar(8));
SQL> insert into table1 values(鈥檞eather鈥?;
SQL> insert into table1 values(鈥檞ether鈥?;
SQL> insert into table1 values(鈥檊ao鈥?;
SQL> select xm from table1 where soundex(xm)=soundex(鈥檞eather鈥?;
XM
--------
weather
wether
14.TRIM(鈥檚鈥?from 鈥檚tring鈥?
LEADING 鍓帀鍓嶉潰鐨勫瓧絎?
TRAILING 鍓帀鍚庨潰鐨勫瓧絎?
濡傛灉涓嶆寚瀹?榛樿涓虹┖鏍肩
15.ABS
榪斿洖鎸囧畾鍊肩殑緇濆鍊?
SQL> select abs(100),abs(-100) from dual;
ABS(100) ABS(-100)
--------- ---------
100 100
16.ACOS
緇欏嚭鍙嶄綑寮︾殑鍊?
SQL> select acos(-1) from dual;
ACOS(-1)
---------
3.1415927
17.ASIN
緇欏嚭鍙嶆寮︾殑鍊?
SQL> select asin(0.5) from dual;
ASIN(0.5)
---------
.52359878
18.ATAN
榪斿洖涓涓暟瀛楃殑鍙嶆鍒囧?
SQL> select atan(1) from dual;
ATAN(1)
---------
.78539816
19.CEIL
榪斿洖澶т簬鎴栫瓑浜庣粰鍑烘暟瀛楃殑鏈灝忔暣鏁?
SQL> select ceil(3.1415927) from dual;
CEIL(3.1415927)
---------------
4
20.COS
榪斿洖涓涓粰瀹氭暟瀛楃殑浣欏雞
SQL> select cos(-3.1415927) from dual;
COS(-3.1415927)
---------------
-1
21.COSH
榪斿洖涓涓暟瀛楀弽浣欏雞鍊?
SQL> select cosh(20) from dual;
COSH(20)
---------
242582598
22.EXP
榪斿洖涓涓暟瀛梕鐨刵嬈℃柟鏍?
SQL> select exp(2),exp(1) from dual;
EXP(2) EXP(1)
--------- ---------
7.3890561 2.7182818
23.FLOOR
瀵圭粰瀹氱殑鏁板瓧鍙栨暣鏁?
SQL> select floor(2345.67) from dual;
FLOOR(2345.67)
--------------
2345
24.LN
榪斿洖涓涓暟瀛楃殑瀵規暟鍊?
SQL> select ln(1),ln(2),ln(2.7182818) from dual;
LN(1) LN(2) LN(2.7182818)
--------- --------- -------------
0 .69314718 .99999999
25.LOG(n1,n2)
榪斿洖涓涓互n1涓哄簳n2鐨勫鏁?
SQL> select log(2,1),log(2,4) from dual;
LOG(2,1) LOG(2,4)
--------- ---------
0 2
26.MOD(n1,n2)
榪斿洖涓涓猲1闄や互n2鐨勪綑鏁?
SQL> select mod(10,3),mod(3,3),mod(2,3) from dual;
MOD(10,3) MOD(3,3) MOD(2,3)
--------- --------- ---------
1 0 2
27.POWER
榪斿洖n1鐨刵2嬈℃柟鏍?
SQL> select power(2,10),power(3,3) from dual;
POWER(2,10) POWER(3,3)
----------- ----------
1024 27
28.ROUND鍜孴RUNC
鎸夌収鎸囧畾鐨勭簿搴﹁繘琛岃垗鍏?
SQL> select round(55.5),round(-55.4),trunc(55.5),trunc(-55.5) from dual;
ROUND(55.5) ROUND(-55.4) TRUNC(55.5) TRUNC(-55.5)
----------- ------------ ----------- ------------
56 -55 55 -55
29.SIGN
鍙栨暟瀛梟鐨勭鍙?澶т簬0榪斿洖1,灝忎簬0榪斿洖-1,絳変簬0榪斿洖0
SQL> select sign(123),sign(-100),sign(0) from dual;
SIGN(123) SIGN(-100) SIGN(0)
--------- ---------- ---------
1 -1 0
30.SIN
榪斿洖涓涓暟瀛楃殑姝ｅ雞鍊?
SQL> select sin(1.57079) from dual;
SIN(1.57079)
------------
1
31.SIGH
榪斿洖鍙屾洸姝ｅ雞鐨勫?
SQL> select sin(20),sinh(20) from dual;
SIN(20) SINH(20)
--------- ---------
.91294525 242582598
32.SQRT
榪斿洖鏁板瓧n鐨勬牴
SQL> select sqrt(64),sqrt(10) from dual;
SQRT(64) SQRT(10)
--------- ---------
8 3.1622777
33.TAN
榪斿洖鏁板瓧鐨勬鍒囧?
SQL> select tan(20),tan(10) from dual;
TAN(20) TAN(10)
--------- ---------
2.2371609 .64836083
34.TANH
榪斿洖鏁板瓧n鐨勫弻鏇叉鍒囧?
SQL> select tanh(20),tan(20) from dual;
TANH(20) TAN(20)
--------- ---------
1 2.2371609
35.TRUNC
鎸夌収鎸囧畾鐨勭簿搴︽埅鍙栦竴涓暟
SQL> select trunc(124.1666,-2) trunc1,trunc(124.16666,2) from dual;
TRUNC1 TRUNC(124.16666,2)
--------- ------------------
100 124.16
36.ADD_MONTHS
澧炲姞鎴栧噺鍘繪湀浠?
SQL> select to_char(add_months(to_date(鈥?99912鈥?鈥檡yyymm鈥?,2),鈥檡yyymm鈥? from dual;
TO_CHA
------
200002
SQL> select to_char(add_months(to_date(鈥?99912鈥?鈥檡yyymm鈥?,-2),鈥檡yyymm鈥? from dual;
TO_CHA
------
199910
37.LAST_DAY
榪斿洖鏃ユ湡鐨勬渶鍚庝竴澶?
SQL> select to_char(sysdate,鈥檡yyy.mm.dd鈥?,to_char((sysdate)+1,鈥檡yyy.mm.dd鈥? from dual;
TO_CHAR(SY TO_CHAR((S
---------- ----------
2004.05.09 2004.05.10
SQL> select last_day(sysdate) from dual;
LAST_DAY(S
----------
31-5鏈?-04
38.MONTHS_BETWEEN(date2,date1)
緇欏嚭date2-date1鐨勬湀浠?
SQL> select months_between(鈥?9-12鏈?1999鈥?鈥?9-3鏈?1999鈥? mon_between from dual;
MON_BETWEEN
-----------
9
SQL>selectmonths_between(to_date(鈥?000.05.20鈥?鈥檡yyy.mm.dd鈥?,to_date(鈥?005.05.20鈥?鈥檡yyy.mm.dd鈥?) mon_betw from dual;
MON_BETW
---------
-60
39.NEW_TIME(date,鈥檛his鈥?鈥檛hat鈥?
緇欏嚭鍦╰his鏃跺尯=other鏃跺尯鐨勬棩鏈熷拰鏃墮棿
SQL> select to_char(sysdate,鈥檡yyy.mm.dd hh24:mi:ss鈥? bj_time,to_char(new_time
2 (sysdate,鈥橮DT鈥?鈥橤MT鈥?,鈥檡yyy.mm.dd hh24:mi:ss鈥? los_angles from dual;
BJ_TIME LOS_ANGLES
------------------- -------------------
2004.05.09 11:05:32 2004.05.09 18:05:32
40.NEXT_DAY(date,鈥檇ay鈥?
緇欏嚭鏃ユ湡date鍜屾槦鏈焫涔嬪悗璁＄畻涓嬩竴涓槦鏈熺殑鏃ユ湡
SQL> select next_day(鈥?8-5鏈?2001鈥?鈥欐槦鏈熶簲鈥? next_day from dual;
NEXT_DAY
----------
25-5鏈?-01
41.SYSDATE
鐢ㄦ潵寰楀埌緋葷粺鐨勫綋鍓嶆棩鏈?
SQL> select to_char(sysdate,鈥檇d-mm-yyyy day鈥? from dual;
TO_CHAR(SYSDATE,鈥?
-----------------
09-05-2004 鏄熸湡鏃?
trunc(date,fmt)鎸夌収緇欏嚭鐨勮姹傚皢鏃ユ湡鎴柇,濡傛灉fmt=鈥檓i鈥欒〃紺轟繚鐣欏垎,鎴柇縐?
SQL> select to_char(trunc(sysdate,鈥檋h鈥?,鈥檡yyy.mm.dd hh24:mi:ss鈥? hh,
2 to_char(trunc(sysdate,鈥檓i鈥?,鈥檡yyy.mm.dd hh24:mi:ss鈥? hhmm from dual;
HH HHMM
------------------- -------------------
2004.05.09 11:00:00 2004.05.09 11:17:00
42.CHARTOROWID
灝嗗瓧絎︽暟鎹被鍨嬭漿鎹負ROWID綾誨瀷
SQL> select rowid,rowidtochar(rowid),ename from scott.emp;
ROWID ROWIDTOCHAR(ROWID) ENAME
------------------ ------------------ ----------
AAAAfKAACAAAAEqAAA AAAAfKAACAAAAEqAAA SMITH
AAAAfKAACAAAAEqAAB AAAAfKAACAAAAEqAAB ALLEN
AAAAfKAACAAAAEqAAC AAAAfKAACAAAAEqAAC WARD
AAAAfKAACAAAAEqAAD AAAAfKAACAAAAEqAAD JONES
43.CONVERT(c,dset,sset)
灝嗘簮瀛楃涓?sset浠庝竴涓璦瀛楃闆嗚漿鎹㈠埌鍙︿竴涓洰鐨刣set瀛楃闆?
SQL> select convert(鈥檚trutz鈥?鈥檞e8hp鈥?鈥檉7dec鈥? "conversion" from dual;
conver
------
strutz
44.HEXTORAW
灝嗕竴涓崄鍏繘鍒舵瀯鎴愮殑瀛楃涓茶漿鎹負浜岃繘鍒?
45.RAWTOHEXT
灝嗕竴涓簩榪涘埗鏋勬垚鐨勫瓧絎︿覆杞崲涓哄崄鍏繘鍒?
46.ROWIDTOCHAR
灝哛OWID鏁版嵁綾誨瀷杞崲涓哄瓧絎︾被鍨?
47.TO_CHAR(date,鈥檉ormat鈥?
SQL> select to_char(sysdate,鈥檡yyy/mm/dd hh24:mi:ss鈥? from dual;
TO_CHAR(SYSDATE,鈥橸Y
-------------------
2004/05/09 21:14:41
48.TO_DATE(string,鈥檉ormat鈥?
灝嗗瓧絎︿覆杞寲涓篛RACLE涓殑涓涓棩鏈?
49.TO_MULTI_BYTE
灝嗗瓧絎︿覆涓殑鍗曞瓧鑺傚瓧絎﹁漿鍖栦負澶氬瓧鑺傚瓧絎?
SQL> select to_multi_byte(鈥欓珮鈥? from dual;
TO
--
楂?
50.TO_NUMBER
灝嗙粰鍑虹殑瀛楃杞崲涓烘暟瀛?
SQL> select to_number(鈥?999鈥? year from dual;
YEAR
---------
1999
51.BFILENAME(dir,file)
鎸囧畾涓涓閮ㄤ簩榪涘埗鏂囦歡
SQL>insert into file_tb1 values(bfilename(鈥檒ob_dir1鈥?鈥檌mage1.gif鈥?);
52.CONVERT(鈥檟鈥?鈥檇esc鈥?鈥檚ource鈥?
灝唜瀛楁鎴栧彉閲忕殑婧恠ource杞崲涓篸esc
SQL> select sid,serial#,username,decode(command,
2 0,鈥檔one鈥?
3 2,鈥檌nsert鈥?
4 3,
5 鈥檚elect鈥?
6 6,鈥檜pdate鈥?
7 7,鈥檇elete鈥?
8 8,鈥檇rop鈥?
9 鈥檕ther鈥? cmd from v$session where type!=鈥檅ackground鈥?
SID SERIAL# USERNAME CMD
--------- --------- ------------------------------ ------
1 1 none
2 1 none
3 1 none
4 1 none
5 1 none
6 1 none
7 1275 none
8 1275 none
9 20 GAO select
10 40 GAO none
53.DUMP(s,fmt,start,length)
DUMP鍑芥暟浠mt鎸囧畾鐨勫唴閮ㄦ暟瀛楁牸寮忚繑鍥炰竴涓猇ARCHAR2綾誨瀷鐨勫?
SQL> col global_name for a30
SQL> col dump_string for a50
SQL> set lin 200
SQL> select global_name,dump(global_name,1017,8,5) dump_string from global_name;
GLOBAL_NAME DUMP_STRING
------------------------------ --------------------------------------------------
ORACLE.WORLD Typ=1 Len=12 CharacterSet=ZHS16GBK: W,O,R,L,D
54.EMPTY_BLOB()鍜孍MPTY_CLOB()
榪欎袱涓嚱鏁伴兘鏄敤鏉ュ澶ф暟鎹被鍨嬪瓧孌佃繘琛屽垵濮嬪寲鎿嶄綔鐨勫嚱鏁?
55.GREATEST
榪斿洖涓緇勮〃杈懼紡涓殑鏈澶у?鍗蟲瘮杈冨瓧絎︾殑緙栫爜澶у皬.
SQL> select greatest(鈥橝A鈥?鈥橝B鈥?鈥橝C鈥? from dual;
GR
--
AC
SQL> select greatest(鈥欏晩鈥?鈥欏畨鈥?鈥欏ぉ鈥? from dual;
GR
--
澶?
56.LEAST
榪斿洖涓緇勮〃杈懼紡涓殑鏈灝忓?
SQL> select least(鈥欏晩鈥?鈥欏畨鈥?鈥欏ぉ鈥? from dual;
LE
--
鍟?
57.UID
榪斿洖鏍囪瘑褰撳墠鐢ㄦ埛鐨勫敮涓鏁存暟
SQL> show user
USER 涓?GAO"
SQL> select username,user_id from dba_users where user_id=uid;
USERNAME USER_ID
------------------------------ ---------
GAO 25
58.USER
榪斿洖褰撳墠鐢ㄦ埛鐨勫悕瀛?
SQL> select user from dual;
USER
------------------------------
GAO
59.USEREVN
榪斿洖褰撳墠鐢ㄦ埛鐜鐨勪俊鎭?opt鍙互鏄?
ENTRYID,SESSIONID,TERMINAL,ISDBA,LABLE,LANGUAGE,CLIENT_INFO,LANG,VSIZE
ISDBA 鏌ョ湅褰撳墠鐢ㄦ埛鏄惁鏄疍BA濡傛灉鏄垯榪斿洖true
SQL> select userenv(鈥檌sdba鈥? from dual;
USEREN
------
FALSE
SQL> select userenv(鈥檌sdba鈥? from dual;
USEREN
------
TRUE
SESSION
榪斿洖浼氳瘽鏍囧織
SQL> select userenv(鈥檚essionid鈥? from dual;
USERENV(鈥橲ESSIONID鈥?
--------------------
152
ENTRYID
榪斿洖浼氳瘽浜哄彛鏍囧織
SQL> select userenv(鈥檈ntryid鈥? from dual;
USERENV(鈥橢NTRYID鈥?
------------------
0
INSTANCE
榪斿洖褰撳墠INSTANCE鐨勬爣蹇?
SQL> select userenv(鈥檌nstance鈥? from dual;
USERENV(鈥橧NSTANCE鈥?
-------------------
1
LANGUAGE
榪斿洖褰撳墠鐜鍙橀噺
SQL> select userenv(鈥檒anguage鈥? from dual;
USERENV(鈥橪ANGUAGE鈥?
----------------------------------------------------
SIMPLIFIED CHINESE_CHINA.ZHS16GBK
LANG
榪斿洖褰撳墠鐜鐨勮璦鐨勭緝鍐?
SQL> select userenv(鈥檒ang鈥? from dual;
USERENV(鈥橪ANG鈥?
----------------------------------------------------
ZHS
TERMINAL
榪斿洖鐢ㄦ埛鐨勭粓绔垨鏈哄櫒鐨勬爣蹇?
SQL> select userenv(鈥檛erminal鈥? from dual;
USERENV(鈥橳ERMINA
----------------
GAO
VSIZE(X)
榪斿洖X鐨勫ぇ灝?瀛楄妭)鏁?
SQL> select vsize(user),user from dual;
VSIZE(USER) USER
----------- ------------------------------
6 SYSTEM
60.AVG(DISTINCT|ALL)
all琛ㄧず瀵規墍鏈夌殑鍊兼眰騫沖潎鍊?distinct鍙涓嶅悓鐨勫兼眰騫沖潎鍊?
SQLWKS> create table table3(xm varchar(8),sal number(7,2));
璇彞宸插鐞嗐?
SQLWKS> insert into table3 values(鈥檊ao鈥?1111.11);
SQLWKS> insert into table3 values(鈥檊ao鈥?1111.11);
SQLWKS> insert into table3 values(鈥檢hu鈥?5555.55);
SQLWKS> commit;
SQL> select avg(distinct sal) from gao.table3;
AVG(DISTINCTSAL)
----------------
3333.33
SQL> select avg(all sal) from gao.table3;
AVG(ALLSAL)
-----------
2592.59
61.MAX(DISTINCT|ALL)
姹傛渶澶у?ALL琛ㄧず瀵規墍鏈夌殑鍊兼眰鏈澶у?DISTINCT琛ㄧず瀵逛笉鍚岀殑鍊兼眰鏈澶у?鐩稿悓鐨勫彧鍙栦竴嬈?
SQL> select max(distinct sal) from scott.emp;
MAX(DISTINCTSAL)
----------------
5000
62.MIN(DISTINCT|ALL)
姹傛渶灝忓?ALL琛ㄧず瀵規墍鏈夌殑鍊兼眰鏈灝忓?DISTINCT琛ㄧず瀵逛笉鍚岀殑鍊兼眰鏈灝忓?鐩稿悓鐨勫彧鍙栦竴嬈?
SQL> select min(all sal) from gao.table3;
MIN(ALLSAL)
-----------
1111.11
63.STDDEV(distinct|all)
姹傛爣鍑嗗樊,ALL琛ㄧず瀵規墍鏈夌殑鍊兼眰鏍囧噯宸?DISTINCT琛ㄧず鍙涓嶅悓鐨勫兼眰鏍囧噯宸?
SQL> select stddev(sal) from scott.emp;
STDDEV(SAL)
-----------
1182.5032
SQL> select stddev(distinct sal) from scott.emp;
STDDEV(DISTINCTSAL)
-------------------
1229.951
64.VARIANCE(DISTINCT|ALL)
姹傚崗鏂瑰樊
SQL> select variance(sal) from scott.emp;
VARIANCE(SAL)
-------------
1398313.9
65.GROUP BY
涓昏鐢ㄦ潵瀵逛竴緇勬暟榪涜緇熻
SQL> select deptno,count(*),sum(sal) from scott.emp group by deptno;
DEPTNO COUNT(*) SUM(SAL)
--------- --------- ---------
10 3 8750
20 5 10875
30 6 9400
66.HAVING
瀵瑰垎緇勭粺璁″啀鍔犻檺鍒舵潯浠?
SQL> select deptno,count(*),sum(sal) from scott.emp group by deptno having count(*)>=5;
DEPTNO COUNT(*) SUM(SAL)
--------- --------- ---------
20 5 10875
30 6 9400
SQL> select deptno,count(*),sum(sal) from scott.emp having count(*)>=5 group by deptno ;
DEPTNO COUNT(*) SUM(SAL)
--------- --------- ---------
20 5 10875
30 6 9400
67.ORDER BY
鐢ㄤ簬瀵規煡璇㈠埌鐨勭粨鏋滆繘琛屾帓搴忚緭鍑?
SQL> select deptno,ename,sal from scott.emp order by deptno,sal desc;
DEPTNO ENAME SAL
--------- ---------- ---------
10 KING 5000
10 CLARK 2450
10 MILLER 1300
20 SCOTT 3000
20 FORD 3000
20 JONES 2975
20 ADAMS 1100
20 SMITH 800
30 BLAKE 2850
30 ALLEN 1600
30 TURNER 1500
30 WARD 1250
30 MARTIN 1250
30 JAMES 950
聽
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鍏堟潵鐪嬬湅瀹冪殑鐢ㄦ硶 decode(鏉′歡,鍊?,緲昏瘧鍊?,鍊?,緲昏瘧鍊?,...鍊糿,緲昏瘧鍊糿,緙虹渷鍊?
瀹冪殑鎰忔濅篃灝辨槸榪欐牱
IF 鏉′歡=鍊? THEN
銆銆銆銆RETURN(緲昏瘧鍊?)
ELSIF 鏉′歡=鍊? THEN
銆銆銆銆RETURN(緲昏瘧鍊?)
銆銆銆銆......
ELSIF 鏉′歡=鍊糿 THEN
銆銆銆銆RETURN(緲昏瘧鍊糿)
ELSE
銆銆銆銆RETURN(緙虹渷鍊?
END IF
閭ｈ繖涓湁浠涔堢敤鍛?鐢ㄥ鍙氨澶т簡.姣旀柟璇?select count(*) from news
鎴戜滑緇熻NEWS涓殑鏂伴椈鏉℃暟,濡傛灉澶т簬1000 鐨勮瘽灝辨彁紺哄ぇ浜庨檺鍒朵簡.
榪欐牱 select decode(count(*),1000,'宸辯粡瓚呭嚭闄愬埗',limit)
榪欐牱limit 杈撳嚭鐨勫氨涓?宸辯粡瓚呭嚭闄愬埗'榪欎釜瀛楃涓?
鎴戜滑榪樺彲浠ョ敤榪欎釜鍒ゆ柇澶у皬
a=10錛屽彉閲廱=20
鍒檚ign(a-b)榪斿洖-1錛宒ecode瑙ｇ爜緇撴灉涓衡滃彉閲?鈥濓紝杈懼埌浜嗗彇杈冨皬鍊肩殑鐩殑銆?
sign()鍑芥暟鏍規嵁鏌愪釜鍊兼槸0銆佹鏁拌繕鏄礋鏁幫紝鍒嗗埆榪斿洖0銆?銆?1
decode(sign(a-b),-1,a,b)
濡傛灉a<b鐨勮瘽,灝辮緭鍑篈鐨勫?
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