Oracle get DISTINCT numeric with a CLOB in the query

Question

EDIT: I am looking for a DISTINCT NUMERIC while including a CLOB within the query.

I have two relations.

Relation One:

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Answer 1

If you hash the clob, you can use it in a subquery to grab the max rowid for each eventid_nbr with the same clob hash value. Then you just filter your relation_two table in the where clause.

SELECT EVENTID_NBR, INPUT_ARGS 

FROM RELATION_ONE, RELATION_TWO 

WHERE RELATION_ONE.LOGID_NBR = RELATION_TWO.LOGID_NBR AND 
  EVENTID_NBR BETWEEN 143 AND 192 AND 
  EVENTID_NBR != 172 AND SYSDATE - 7 >= RELATION_ONE.LAST_UPDATED

  AND (RELATION_TWO.EVENTID_NBR, RELATION_TWO.ROWID) IN
      (SELECT DISTINCT EVENTID_NBR,
       MAX(ROWID) OVER (PARTITION BY EVENTID_NBR, DBMS_HASH(INPUT_ARGS,3))
       FROM RELATION_TWO);

The 3 in the HASH specified SHA, but you can also use MD4 (1) or MD5 (2) if you like.

I'm thinking this could be very slow if you have a lot of rows in the RELATION_TWO table and I'm sure this can be written to perform better, but the concept is sound.