Question

Can “Distinct” key Word be used twice in a single Select Query? like wise:

select DISTINCT(trackid), DISTINCT(table_name) 
from jos_audittrail 
where live = 0 AND operation = UPDATE

Thanks

Answer 1

No, By Default Distinct works on all the columns you are selecting.
eg.

select DISTINCT trackid, table_name 
from jos_audittrail 
where live = 0 AND operation = UPDATE

This will select all distinct trackid and table name combination

EDIT

For retrieving distinct records other than this you can use the answer given by davek. It will work.

You can use group by to do this work as group by is being applied on both the columns being provided so no aggregate function is needed.

    SELECT trackid, table_name FROM jos_audittrail 
    WHERE live = 0 AND operation = 'UPDATE' 
    GROUP BY trackid, tablename