ORACLEº¯Êý´óÈ«

SQLÖеĵ¥¼Ç¼º¯Êý
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')
string Ï£Íû±»Ìæ»»µÄ×Ö·û»ò±äÁ