hive中 regexp_replace的用法，替換特殊字符問題

數據倉庫中有的字段不合格，有特殊字符，比如換行符。

poi_name
\n19013
\n12013

怎么把換行符替換掉呢？

https://cwiki.apache.org/confluence/display/Hive/LanguageManual+UDF#LanguageManualUDF-StringOperators

regexp_replace(string INITIAL_STRING, string PATTERN, string REPLACEMENT)

Returns the string resulting from replacing all substrings in INITIAL_STRING that match the java regular expression syntax defined in PATTERN with instances of REPLACEMENT. For example, regexp_replace("foobar", "oo|ar", "") returns 'fb.' Note that some care is necessary in using predefined character classes: using '\s' as the second argument will match the letter s; '\s' is necessary to match whitespace, etc.

官網說用兩個反斜杠代替一個，即一個反斜杠用來轉義。

實踐了一下，不行，得4個

select regexp_replace(poi_name,'\\\\n','') 

poi_name
19013
12013