Tagged Questions
0
votes
1answer
38 views
Index on a query with order
I have the following table with >1M rows:
CREATE TABLE `wishlist_place` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`wishlist_id` int(11) DEFAULT NULL,
`place_id` int(11) DEFAULT NULL,
`city_id` ...
1
vote
1answer
168 views
db INDEX on ORDER BY FIELD in very simple query does not help - still slow response?
I have very simple query which returns 200K records very slow (20 seconds).
SELECT * FROM TABLE ORDER BY ID DESC
If I do just
SELECT * FROM TABLE
it returns quick result.
I created INDEX on ...
6
votes
1answer
206 views
Must an index cover all selected columns for it to be used for ORDER BY?
Over at SO, someone recently asked Why isn't ORDER BY using the index?
The situation involved a simple InnoDB table in MySQL comprising three columns and 10k rows. One of the columns, an integer, ...
0
votes
1answer
39 views
Is index like key(timetime) usable when we query: SELECT * … ORDER BY timetime DESC
When we index a timestamp field like timetime. Can we use it for ORDER BY timetime DESC or is it just usable for ORDER BY timetime ASC OR ORDER BY timetime? Does mySQL use this index when doing vise ...
9
votes
1answer
2k views
Order by column should have index or not?
I have added indexes to table which are used for searching result. I am showing results by ASC or DESC order. So that column should have index or not? I have 2 more indexes on that table. How ...
