Question

Oracle 怎样去掉末尾的几个字母

Answer 1

用 substr

比如：substr(colname,1,length(colname) - 3)

oracle的substr函数的用法
取得字符串中指定起始位置和长度的字符串 substr( string, start_position, [ length ] )
如:
substr('This is a test', 6, 2) would return 'is'
substr('This is a test', 6) would return 'is a test'
substr('TechOnTheNet', -3, 3) would return 'Net'
substr('TechOnTheNet', -6, 3) would return 'The'
select substr('Thisisatest', -4, 2) value from dual 结果是 te
select substr('emros',-3,1) value from dual 结果是 r

substr('abcde',-6) = null
substr('abcde',-5) = 'abcde'
substr('abcde',-4) = 'bcde'
substr('abcde',-3) = 'cde'
substr('abcde',-2) = 'de'
substr('abcde',-1) = 'e'
substr('abcde',-0) = 'abcde'

Answer 2

replace(x,y,z)返回值为将串X中的Y串用Z串替换后的结果字符串

"REPLACE"(source, search_str, replace_str)
"REPLACE"('THIS IS A ***', '***', '')就把***去掉了
其实就是把***换为空值
你可以把***换为你要去掉的字母