tokenize string to use in oracle WHERE... IN clause. reference: https://blogs.oracle.com/aramamoo/entry/how_to_split_comma_separated_string_and_pass_to_in_clause_of_select_statement

oracle tokenize string.sql

-- '1,2,3' is the list of ids we would be searching against
SELECT  *
FROM    table
WHERE   id IN
        (
            SELECT REGEXP_SUBSTR('1,2,3','[^,]+', 1, level) from dual
            CONNECT BY REGEXP_SUBSTR('1,2,3', '[^,]+', 1, level) is not null
        )