SELECT
PROCESS_ID,
COUNT(b.PROCESS_ID) AS CNT
FROM
(
    SELECT
    SESSION_ID,
    PROCESS_ID,
    STEPOUT,
    COUNT,
    COUNT(PROCESS_ID) OVER(partition by SESSION_ID order by EX_TIMESTAMP) AS COUNT2
    FROM
    (
        SELECT  SESSION_ID,
            PROCESS_ID,
            EX_TIMESTAMP,
            SUBSTR(PROCESS_ID, 5, 1) AS STEPOUT,
            COUNT(PROCESS_ID) OVER(partition by SESSION_ID order by EX_TIMESTAMP) AS COUNT
        FROM    PROCESS_LOG
    ) a
    WHERE   CAST(COUNT as string) = CAST(STEPOUT AS string)
) b
WHERE COUNT = COUNT2
GROUP BY b.PROCESS_ID
ORDER BY PROCESS_ID ASC