[20260227]使用trim函数删除前后字符.txt

[20260227]使用trim函数删除前后字符.txt --//想使用trim函数删除前后字符，缺省仅仅删除空格，如果不是空格写法比较特殊，做1个记录。 1.环境： SCOTT@book01p> @ ver2 ============================== PORT_STRING                   : x86_64/Linux 2.4.xx VERSION                       : 21.0.0.0.0 BANNER                        : Oracle Database 21c Enterprise Edition Release 21.0.0.0.0 - Production BANNER_FULL                   : Oracle Database 21c Enterprise Edition Release 21.0.0.0.0 - Production Version 21.3.0.0.0 BANNER_LEGACY                 : Oracle Database 21c Enterprise Edition Release 21.0.0.0.0 - Production CON_ID                        : 0 PL/SQL procedure successfully completed. 2.测试： SCOTT@book01p> select trim('  aaa,bbb ')||'z' c20 from dual ; C20 -------------------- aaa,bbbz --//删除前后空格很简单，直接使用trim函数。 --//如果要删除前后逗号，这样写报错。 SCOTT@book01p> select trim(',,,,aaa,bbb,,,',',')||'z' c20 from dual ; select trim(',,,,aaa,bbb,,,',',')||'z' c20 from dual                             * ERROR at line 1: ORA-00907: missing right parenthesis --//要写出如下： SCOTT@book01p> select trim(',' from  ',,,,aaa,bbb,,,')||'z' c20 from dual ; C20 -------------------- aaa,bbbz --//第1个参数仅仅接受1个字符。 SCOTT@book01p> select trim('ab' from  ',,,,aaa,bbb,,,')||'z' c20 from dual ; select trim('ab' from  ',,,,aaa,bbb,,,')||'z' c20 from dual        * ERROR at line 1: ORA-30001: trim set should have only one character --//当然还有1个笨的方法使用ltrim+rtrim函数。 SCOTT@book01p> select rtrim(ltrim(',,,,aaa,bbb,,,',','),',')||'z' c20 from dual ; C20 -------------------- aaa,bbbz