Question

I am not sure if this is possible but here goes.

I am using MySQL and need to complete a statement that produces an output as follows.

I have a table which contains a completeddate field and an enquirydate field.

I need to get data on the time difference between theses fields for which I have the following code

SELECT DATE (completedate) - DATE (enqdate) AS `timediff`, COUNT(*) AS TotalCount
FROM cia_enquiry
WHERE (DATEDIFF(CURDATE(), enqdate) < 30) AND completedate > 1
GROUP BY `timediff`
ORDER BY `timediff` ASC

The above code simply outputs a figure of days between the dates and the total count of entires within the last 30 days (and not counting those entries that are not complete)

I now need to reference the “timediff” results against another table and pull another field from that table.

For example if timediff = 1, then we need to find the id of 1 in another table and return the description field from this table.

Ultimately we should end up with something similar to

---

timediff     TotalCount         description
0               52                      Within 24 hrs
1               13                      24-48hrs
etc etc ………

Answer 1

It can be done; you have two choices

1. Create a temporary table with the result of your query and then join this table with your second table
2. Use your first query as a subquery and join it with your second table

Option 1

create temporary table temp_tbl
select
   ...
;
# Important: create the indexes you need
alter table temp_tbl
   add index index1(field1), ... ;
# Now join your second table
select a.*, b.*
from temp_tbl as a join tbl2 as b on ...;

Option 2

select a.*, b.*
from (
    select ... # here is your query
    ) as a join tbl2 as b on ...

Hope this helps you