Question

Following is my table schema.

Channel listing table:

    CHAN_NUMBER  CHAN_NAME   CHAN_TYPE
 ----------- -----------------------------------
      1 MTV                   Music
      2 ESPN                  Sports
      3 TNT                   Movies
      4 Fox                   Movies
      5 Fox                   Sports

customer survey table:

   SURV_ID SURV_DATE SURV_FAV_CHAN CUST_NUMBER
 ---------- --------- ------------- -----------
     1     25-NOV-12             1           2
     2     24-NOV-12             2           1
     3     24-NOV-12             3           3
     4     24-NOV-12             4           4
     5     24-NOV-12             5           5
     6     24-NOV-12             1           6
     7     24-NOV-12             2           7
     8     24-NOV-12             3           8
     9     24-NOV-12             4           9
    10     24-NOV-12             5          10
    11     24-NOV-12             1          11

I have these two tables that I need to generate a report that lists every channel and a count of how many customers have selected that channel as their favorite.

On oracle database I got up to the point where I am generating a count of each time a channel was selected as a favorite from the SURVEY table. But I can’t figure out how to join them to create a list of channels displaying the channel number, the name and the count of customers who chose it as their favorite.

-- my channel table query


SELECT CHAN_NUMBER, CHAN_NAME FROM CHANNEL;


-- here is how I'm generating the couNt


SELECT COUNT(SURV_FAV_CHAN) FROM SURVEY
GROUP BY SURV_FAV_CHAN HAVING COUNT(SURV_FAV_CHAN) > 1;

ANY HELP WOULD BE AWESOME.

Answer 1

You can try something like this:

SELECT MAX(CH.CHAN_NUMBER), MAX(CH.CHAN_NAME), COUNT(SRV.SURV_FAV_CHAN) FROM SURVEY SRV  
LEFT JOIN CHANNEL CH ON CH.CHAN_NUMBER = SRV.SURV_FAV_CHAN
GROUP BY SRV.SURV_FAV_CHAN HAVING COUNT(SRV.SURV_FAV_CHAN) > 1;

And you may want to use SUM(SRV.SURV_FAV_CHAN) if you really need the total amount of customers if I understand you question correctly