一、问题描述
今天碰到个问题,有个列中的字段前后都有不同数量的空格,开发人员要求去掉这些空格。其实ORACLE早就替我们准备好trim函数来处理这样的问题。让我们实验一下,学习记住trim这个小东东。
二、实验
1.创建测试数据
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SAM@OCM11G >create table test_space(id int,name varchar2(10));
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Table created.
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SAM@OCM11G >insert into test_space values (1,'sam');
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1 row created.
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SAM@OCM11G >insert into test_space values (2,' sam ');
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1 row created.
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SAM@OCM11G >insert into test_space values (3,' sam ');
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1 row created.
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SAM@OCM11G >commit;
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Commit complete.
2.查询数据发现问题,并做字符统计
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SAM@OCM11G >select * from test_space;
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ID NAME
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---------- ----------
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1 sam
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2 sam
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3 sam
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SAM@OCM11G >select id,length(name) from test_space;
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ID LENGTH(NAME)
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---------- ------------
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1 3
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2 5
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3 8
3.使用trim去掉空格
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SAM@OCM11G >select id,length(trim(name)) from test_space;
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ID LENGTH(TRIM(NAME))
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---------- ------------------
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1 3
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2 3
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3 3
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SAM@OCM11G >update test_space set name=trim(name);
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3 rows updated.
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SAM@OCM11G >select * from test_space;
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ID NAME
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---------- ----------
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1 sam
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2 sam
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3 sam
4.检查(问题已处理)
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SAM@OCM11G >select id,length(name) from test_space;
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ID LENGTH(NAME)
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---------- ------------
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1 3
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2 3
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3 3
三、总结
一个小小的trim函数,真是难者不会,会者不难。通过这个小案例,我又多掌握了ORACLE的一个小功能,学习脚步不能停。好久没有发文了,再给自己一针强心剂。加油 Sam!Where there is a will, there is a way.