110¸öoracle³£Óú¯Êý×ܽá
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 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))
------ ------------ ---------------- ------------ ---------
--------------------
¸ßǬ¾º 3 ±±¾©Êк£¶§Çø 6 9999.99 7
7.LOWER
·µ»Ø×Ö·û´®,²¢½«ËùÓеÄ×Ö·ûСд
SQL> select lower(AaBbCcDd)AaBbCcDd from dual;
AABBCCDD
--------
aabbccdd
8.UPPER
·µ»Ø×Ö·û´®,²¢½«ËùÓеÄ×Ö·û´óд
SQL> select upper(AaBbCcDd) upper from dual;
UPPER
--------
AABBCCDD
9.RPADºÍLPAD(Õ³Ìù×Ö·û)
RPAD ÔÚÁеÄÓÒ±ßÕ³Ìù×Ö·û
LPAD ÔÚÁеÄ×ó±ßÕ³Ìù×Ö·û
SQL> select lpad(rpad(gao,10,*),17,*)from dual;
LPAD(RPAD(GAO,1
-----------------
*******gao*******
²»¹»×Ö·ûÔòÓÃ*À´ÌîÂú
10.LTRIMºÍRTRIM
LTRIM ɾ³ý×ó±ß³öÏÖµÄ×Ö·û´®
RTRIM ɾ³ýÓұ߳öÏÖµÄ×Ö·û´®
SQL> select ltrim(rtrim( gao qian jing , ), ) from dual;
LTRIM(RTRIM(
-------------
gao qian jing
11.SUBSTR(string,start,count)
È¡×Ó×Ö·û´®,´Óstart¿ªÊ¼,È¡count¸ö
SQL> select substr(13088888888,3,8) from dual;
SUBSTR(
--------
08888888
12.REPLACE(string,s1,s2)
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