Bug Report:
Version: 3.23.51-max
OS: Windows ME
Problem:
Synopsis: Does not use index when ordering records on datetime field in
the descending order, even though though this field is NOT NULL.
I created the following table:
CREATE TABLE Threads (threadID int NOT NULL PRIMARY KEY,
forumID int NOT NULL REFERENCES Forums(forumID),
discussion char(100),
starter char(40),
num_replies int,
last_modified datetime NOT NULL,
INDEX (forumID, last_modified));
When I execute the following query with explain word I notice that index
is not used:
explain select * from Threads
where forumID = 1 order by last_modified desc;
If I want to select these records in the ascending order, than the index
IS used.
Thanks,
Greg Vinogradov
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