OracleSQL内置函数大全之一

LTRIM(RTRIM('

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gao qian jing

11.SUBSTR(string,start,count)

取子字符串,从start开始,取count个

SQL> select substr('13088888888',3,8) from dual;

SUBSTR('

--------

08888888

12.REPLACE('string','s1','s2')

string   希望被替换的字符或变量

s1       被替换的字符串

s2       要替换的字符串

SQL> select replace('he love you','he','i') from dual;

REPLACE('HELOVEYOU','HE','I')

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i love you

13.SOUNDEX 返回一个与给定的字符串读音相同的字符串

SQL> create table table1(xm varchar(8));

SQL> insert into table1 values('weather');

SQL> insert into table1 values('wether');

SQL> insert into table1 values('gao');

SQL> select xm from table1 where soundex(xm)=soundex('weather');

XM

--------

weather

wether

14.TRIM('s' from 'string')

LEADING   剪掉前面的字符

TRAILING  剪掉后面的字符

如果不指定,默认为空格符

15.ABS 返回指定值的绝对值

SQL> select abs(100),abs(-100) from dual;

ABS(100) ABS(-100)

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