Hi there,
I am only just learning SQL and have three specific questions on correct
syntax for my queries...
*1.* The 'Data1' and 'Data2' columns have stings which contain both numbers
and letters. In the query below I have removed the letters and re-named the
trimmed versions. I want to cast the remaining numbers to numerics and run
aggregate functions on them (ie AVG, MAX etc). However, whenever I wrap the
TRIM in a function I am getting errors. How do I fix this?
Here is my query
SELECT data1, TRIM(TRAILING ' total bookmarks' FROM data1) as Bookmarks_trim, data2, TRIM(TRAILING ' folders' FROM
data2)as Folders_trim, event_code, user_id
FROM events
WHERE event_code =8
And this is what it returns: http://screencast.com/t/DCvey2sAxZ
*2. *I want to add an additional parameter to the query above to show only
DISTINCT instances of the user_id. The separate query I have for that is
below. How do I combine the two?
SELECT DISTINCT
*
FROM (SELECT DISTINCT user_id, event_code, data1, data2 FROM events) AS temp
WHERE event_code = 8
This returns: http://screencast.com/t/IXhpix0vLNSp
*3. *Lastly, I want to be able to sort by DESC on both the trimmed data1
column and data2 (to see the users with the highest number of folders and
bookmarks) I know you do this with ORDER BY but I am not sure where it would
go in such a large query.
ANY help would be hugely appreciated.
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