How to get part of the string that matched with regular expression in Oracle SQL
One way to do it is with REGEXP_REPLACE. You need to define the whole string as a regex pattern and then use just the element you want as the replace string. In this example the ColorID is the third pattern in the entire string
SELECT REGEXP_REPLACE('product=1627;color=45;size=7' , '(.*)(color\=)([^;]+);?(.*)' , '\3') "colorID" FROM DUAL; It is possible there may be less clunky regex solutions, but this one definitely works. Here's a SQL Fiddle.
From Oracle 11g onwards we can specify capture groups in REGEXP_SUBSTR.
SELECT REGEXP_SUBSTR('product=1627;color=45;size=7', 'color=(\d+);', 1, 1, 'i', 1) "colorID" FROM DUAL;