Question

I am new to SQL and just at a loss for why this piece of code won’t execute. I get know errors but I get no results. No matter how long I wait, the code just keeps processing. I know this problem probably has something to do with my specific database, but I was wondering if there are any overt errors.

Additionally, if it has to do with the call I am making in my database, how would I go about debugging this since I get no formal errors?

SELECT cr.COMMUNICATIONS_ID AS ANSWER_ID, cr.CONSUMER_ID as VIEWER_ID, 
       cr.ACTION_LOG_ID, nc.PARENT_COMMUNICATIONS_ID AS QUESTION_ID,
       cirm.CONSUMER_RATING AS VIEWER_INTEREST, 
       cim.CONSUMER_INTEREST_EXPERT_ID AS DOMAIN
FROM (
       SELECT 234 AS CONSUMER_ID, ACTION_LOG_ID, COMMUNICATIONS_ID 
        FROM consumer_action_log 
        WHERE COMM_TYPE_ID=4
      ) AS cr
    JOIN network_communications AS nc ON 
        cr.COMMUNICATIONS_ID=nc.COMMUNICATIONS_ID
    JOIN communication_interest_mapping AS cim ON 
       nc.PARENT_COMMUNICATIONS_ID=cim.COMMUNICATION_ID
    JOIN consumer_interest_rating_mapping AS cirm ON 
       cr.CONSUMER_ID=cirm.CONSUMER_ID AND           
       cim.CONSUMER_INTEREST_EXPERT_ID=cirm.CONSUMER_INTEREST_ID;

Answer 1

The derived column in the subquery may be throwing MySQL off. Try this query instead for the same results

SELECT cr.COMMUNICATIONS_ID AS ANSWER_ID, cirm.CONSUMER_ID as VIEWER_ID, 
       cr.ACTION_LOG_ID, nc.PARENT_COMMUNICATIONS_ID AS QUESTION_ID,
       cirm.CONSUMER_RATING AS VIEWER_INTEREST, 
       cim.CONSUMER_INTEREST_EXPERT_ID AS DOMAIN
FROM (
       SELECT ACTION_LOG_ID, COMMUNICATIONS_ID 
        FROM consumer_action_log 
        WHERE COMM_TYPE_ID=4
      ) AS cr
    JOIN network_communications AS nc ON 
        cr.COMMUNICATIONS_ID=nc.COMMUNICATIONS_ID
    JOIN communication_interest_mapping AS cim ON 
       nc.PARENT_COMMUNICATIONS_ID=cim.COMMUNICATION_ID
    JOIN consumer_interest_rating_mapping AS cirm ON 
       cim.CONSUMER_INTEREST_EXPERT_ID=cirm.CONSUMER_INTEREST_ID
WHERE cirm.CONSUMER_ID = 234