Ordering a mysql query?
I have 2 tables, Pages and LinkPages.
Within Pages i have the fields:- pageID (the identifier of the page),
- startmemberID (the id of the member that created the page),
- startDate (date the page was created).
In LinkPages I have:
- pageID (to link with the page),
- linkmemberID (member linking with the page),
- joinDate (date member linked with the page).
What sql query would i use to get all information on the pages with a particular id and then order it by the date the page was started.
I got thi开发者_JAVA百科s far:
SELECT * FROM LinkPages WHERE linkmemberID='MEMBERID' LIMIT 5
but obviously i haven't ordered them here, would i need to use a join?
Many Thanks,
Jai
Try this:
SELECT * FROM LinkPages
INNER JOIN Pages ON Pages.pageID = LinkPages.pageID
WHERE linkmemberID='MEMBERID'
ORDER BY startDate DESC
LIMIT 5
SELECT lp.pageID, lp.linkmemberID, lp.joinDate
FROM LinkPages lp, Pages p
WHERE lp.linkmemberID='MEMBERID' AND lp.pageID = p.pageID
ORDER BY p.startDate DESC
LIMIT 5
You have two options, either you can JOIN
or you can use a subquery:
SELECT * FROM LinkPages WHERE linkmemberID='MEMBERID'
ORDER BY
(SELECT startDate FROM Pages WHERE Pages.pageID = LinkPages.PageID) DESC
LIMIT 5
For good measure, here's the join:
-- be sure to use L.* here, otherwise you get all of the columns from
-- pages as well
SELECT L.* FROM LinkPages L
INNER JOIN Pages P ON P.pageID = L.pageID
WHERE linkmemberID='MEMBERID'
ORDER BY P.startDate DESC LIMIT 5
SELECT lp.*
FROM LinkPages lp, Pages p
WHERE lp.pageId = p.pageId
AND lp.linkmemberID='MEMBERID'
ORDER BY p.startDate
LIMIT 5
sorry - forgot the ORDER BY ...
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