用 substr

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

oracle的substr函式的用法

取得字串中指定起始位置和長度的字串 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 結果是 te

select substr("emros",-3,1) value from dual 結果是 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"