oracle培訓教程：單行字符函數(shù)語句用法

Upper

SELECT Upper ('abcde') FROM dual ;

SELECT * FROM emp WHERE ename=UPPER('smith') ;

Lower

SELECT lower('ABCDE') FROM dual ;

Initcap

Select initcap(ename) from emp;

Concat

Select concat("a","b") from dual; Select "a" || "b" from dual;

Substr

Select substr("abcde",length("abcde")-2) from dual; Select substr("abcde",-3,3) from dual;

Length

Select length(ename) from emp;

Replace

Select replace(ename,"a","A") from emp;

Instr

Select instr('Hello World','or') from dual; 8 indexof

Lpad

lpad('Smith',10,'*') 左側(cè)填充 lpad() *****Smith

Rpad

rpad('Smith',10,'*') 右側(cè)填充 rpad()Smith*****

Trim

trim(' Mr Smith ') 過濾首尾空格 trim() Mr Smith