How to use regular expressions to filter data in Hive?

You can use regular expressions to filter data in Hive. Here is a simple example:

Suppose there is a table named user_info, which includes the following data:

id    name
1     Alice
2     Bob
3     Charlie
4     David
5     Eve

If we want to use regular expressions to filter out all users whose names start with the letter “A”, we can achieve this using the RLIKE keyword.

SELECT * FROM user_info WHERE name RLIKE '^A.*';

This query will return the following results:

id    name
1     Alice

In the example above, ‘^A.*’ in RLIKE is a regular expression used to match names that start with the letter “A”. In Hive, the RLIKE keyword is used to determine if a string matches the specified regular expression.