regexp (same as rlike)
| operator | operand types | description |
|---|---|---|
| A rlike B | strings | NULL if A or B is NULL, TRUE if any (possibly empty) substring of A matches the Java regular expression B, otherwise FALSE. For example, 'foobar' RLIKE 'foo' evaluates to TRUE and so does 'foobar' RLIKE '^f.*r$'. |
| A regexp B | strings | same as rlike |
A(string) regexp B(正则表达式)
select * from table_name where column1 regexp '[正则表达式]'
and column2 not regexp '[正则表达式]'
regexp_extract、regexp_replace
| return type | name(signature) | description |
|---|---|---|
| string | regexp_extract(string subject, string pattern, int index) | Returns the string extracted using the pattern. For example, regexp_extract('foothebar', 'foo(.*?)(bar)', 2) returns 'bar.' 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. The 'index' parameter is the Java regex Matcher group() method index. See docs/api/java/util/regex/Matcher.html for more information on the 'index' or Java regex group() method. |
| string | 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. |
参考文献：https://cwiki.apache.org/confluence/display/Hive/LanguageManual+UDF
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