On 3/10/2011 13:12, Jim McNeely wrote:
Shawn,
This is the first thing that I though as well, but here is a portion from the
show create table for patient_:
PRIMARY KEY (`zzk`),
KEY `IdPatient` (`IdPatient`),
KEY `SSN` (`SSN`),
KEY `IdLastword` (`IdLastword`),
KEY `DOB` (`DateOfBirth`),
KEY `NameFirst` (`NameFirst`),
KEY `NameLast` (`NameLast`)
This extremely simple join is still massively slow.
Jim
On Mar 10, 2011, at 10:00 AM, Shawn Green (MySQL) wrote:
On 3/10/2011 12:32, Jim McNeely wrote:
Rhino,
Thanks for the help and time! Actually, I thought the same thing, but what's
weird is that is the only thing that doesn't slow it down. If I take out all of
the join clauses EXCEPT that one the query runs virtually instantaneously. for
some reason it will use the index in that case and it works. If I take out
everything like this:
SELECT a.IdAppt, a.IdPatient,
p.NameLast, p.NameFirst, p.NameMI
from Appt_ a
LEFT JOIN patient_ p
ON a.IdPatient = p.IdPatient
WHERE a.ApptDate>= '2009-03-01';
1) Verify that the indexes on `patient_` haven't been disabled
SHOW INDEXES FROM `patient_`;
http://dev.mysql.com/doc/refman/5.5/en/show-index.html
2) Verify that the data types of `Appt_`.`IdPatient` and
`patient_`.`IdPatient` are not incompatible. (for example: one is
varchar, the other int)
Thanks,
--
Shawn Green
MySQL Principal Technical Support Engineer
Oracle USA, Inc. - Hardware and Software, Engineered to Work Together.
Office: Blountville, TN
--
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe: http://lists.mysql.com/mysql?unsub=arch...@jab.org
