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1.ASCII
·µ»ØÓëÖ¸¶¨µÄ×Ö·û¶ÔÓ¦µÄÊ®½øÖÆÊý;
SQL> select ascii(’A’) A,ascii(’a’) a,ascii(’0’) zero,ascii(’ ’) space from dual;
A A ZERO SPACE
--------- --------- --------- ---------
65 97 48 32
2.CHR
¸ø³öÕûÊý,·µ»Ø¶ÔÓ¦µÄ×Ö·û;
SQL> select chr(54740) zhao,chr(65) chr65 from dual;
ZH C
-- -
ÕÔ A
3.CONCAT
Á¬½ÓÁ½¸ö×Ö·û´®;
SQL> select concat(’010-’,’88888888’)||’ת23’ ¸ßǬ¾ºµç»° from dual;
¸ßǬ¾ºµç»°
----------------
010-88888888ת23
4.INITCAP
·µ»Ø×Ö·û´®²¢½«×Ö·û´®µÄµÚÒ»¸ö×Öĸ±äΪ´óд;
SQL> select initcap(’smith’) upp from dual;
UPP
-----
Smith
5.INSTR(C1,C2,I,J)
ÔÚÒ»¸ö×Ö·û´®ÖÐËÑË÷Ö¸¶¨µÄ×Ö·û,·µ»Ø·¢ÏÖÖ¸¶¨µÄ×Ö·ûµÄλÖÃ;
C1 ±»ËÑË÷µÄ×Ö·û´®
C2 Ï£ÍûËÑË÷µÄ×Ö·û´®
I ËÑË÷µÄ¿ªÊ¼Î»ÖÃ,ĬÈÏΪ1
J ³öÏÖµÄλÖÃ,ĬÈÏΪ1
SQL> select instr(’oracle traning’,’ra’,1,2) instring from dual;
INSTRING
---------
9
6.LENGTH
·µ»Ø×Ö·û´®µÄ³¤¶È;
SQL> select
Ïà¹ØÎĵµ£º
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SQL>SET AUTO[COMMIT] {ON|OFF|IMM[EDIATE]| n}
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SQL> SET ECHO {ON|OFF}
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SQL> SET FEED[BACK] {6|n|ON|OFF}
ĬÈÏÖ»Óн ......
row_number() OVER (PARTITION BY COL1 ORDER BY COL2) ±íʾ¸ù¾ÝCOL1·Ö×飬ÔÚ·Ö×éÄÚ²¿¸ù¾Ý COL2ÅÅÐò£¬¶ø´Ëº¯Êý¼ÆËãµÄÖµ¾Í±íʾÿ×éÄÚ²¿ÅÅÐòºóµÄ˳Ðò±àºÅ£¨×éÄÚÁ¬ÐøµÄΨһµÄ).
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select * from emp where rownum > 5
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student subject grade
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Sql´úÂë
--ɾ³ýij¸öÓû§ÏµĶÔÏó
set heading off;
set feedback off;
spool c:\dropobj.sql;
prompt --Drop constraint
select 'alter t ......