Hive Regex: Extract & Replace Functions

In Hive, you can use the functions regexp_extract() and regexp_replace() for regex matching operations.

1. The function regexp_extract(col, pattern, index) is used to extract the string that matches the regular expression pattern from the specified column (col), and returns the result of the indexth matching group. For example, regexp_extract(‘Hello World’, ‘(\w+) (\w+)’, 2) will return ‘World’.
2. The function regexp_replace(col, pattern, replacement) is used to replace strings in the specified column (col) that match the regular expression (pattern) with the replacement. For example, regexp_replace(‘Hello World’, ‘\w+’, ‘Hi’) will return ‘Hi Hi’.

These two functions can be used for flexible regular expression matching in Hive.