Need Some Help In Improving Performance On A Query (was: Hi People)
I need some help in improving performance on a query which is taking too long to execute.
I have 3 tables:
table 'photo' stores information on photos and it has 2 important fields:
- photo_id
- title
table 'item' stores information on generic items in the system (photos is an example). It has 3 important fields:
- item_id
- item_type (like 'photos')
- submitter_id
table 'user' stores information on users in the system. It has 2 important fields:
- user_id
- name
I would like to get the number of photos that either have a title that contains 'a' or the submitter's name contains 'a'
I tried the following:
SELECT count(DISTINCT photo.photo_id) NumItems
FROM (photo, item, user)
WHERE (item.item_id = photo.photo_id AND
item.item_type = 'photos' AND
(photo.title LIKE '%a%' OR (user.name LIKE '%a%' AND user.user_id = item.submitter_id)));
This query is taking way too long (sometimes up to 10 seconds
Note that I have over 2,000,000 records in the 'user' table (I suspect the problem is there)
I only have 2 recods in the 'photo' table
I only have 2 records in the 'item' table
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I am currently testing replication on mysql 5.0.9 running on Win XP Pro on 2 servers , one as a master , and another as slave , basic master-slave configuration. The slave have 2.5 GigaB of RAM,300GB SATA2 HD & on Intel 2.4ghz Core Duo and the master have 1 GigaB of RAM,200GB SATA HD & on Intel 2.0ghz Core Duo , which means the master server not as powerful as the slave server. Is it OK ? Which one requires more processing load , the master or the slave ? and why if you could explain (or at least provide the link)...
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Problem With MYSQL Performance With ASP.NET
Large table performance problem with MYSQL performance with ASP.NET I am doing some benchmarking of an application using MYSQL under Windows and I confused about the results. Environment Emachine 6417 with amd3200+ 64 bit processor 3.3GB ram mysql 4.1 with odbc 3.51 MYISAM windows 2003 server std edition date, account and invoice number are indexed Database size 18 million rows I am querying (selecting) columns of a date and an account our tester program that opens a socket to the Mysql database and does a select for the above n times each time the date and the account is randomized to minimize hits on records closeby. This program will perform over 1000 queries per second. At the end, the Mysql socket will be closed When I enter a similar query manually a web interface, I get about 3 second response time. This program opens/closes a socket for each query Does anyone have any suggestions Your assistance would be greatly appreciated Also in production, this table will be accesse for both read and write will I have problems. My testing showed that Innodb is much slower.
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MySQL Performance Question..
I'm running a server with a Pentium 133 w/32meg ram, 512 pipeline burst, with a wd 512MB HD and I want to store George Bush in our MySQL database. As far as table definitions are concerned, should I use a BLOB or should I store him on disk and make a reference to the physical location in the MySQL table instead? Will I run into any performance/storage issues when querying this data?
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