Slow Query Execution With Strange Issue
Right now I am fazing one issue which is getting hell out of me. I am explaining the issues step by step.
1.I have one site running from last 3 years with large database and there is one main table which has maximum load.
2.Now, I have redesigned the site with lots of changes within this table too.
3.the problem is that the server is same, queries are same but output in the new database is taking 50 times more time.
I have tried all, compared the structures of the data and table but still the query result is too slow on live testing sever. While same query in main site of same server is running perfectly.
Have any one fazed such and issue? Please help me out of the situation as site is ready but I m not able to put new version live.
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I have a table with ~800,000 records. I need to grab random rows from the table based on certain criteria. The problem is that average lowest subset to grab the random row is around 200k. Here is what I'm trying to do: There are 4 columns: data,n1,n2, and n3. I need to get the value of the data column based on criteria using the n1-n3 columns. The most common query is SELECT data FROM table WHERE n1 = ? The problem is that n1 can be only 1 of 5 possiblities. When the table is finished being populated there will be roughly 1.5 million records and 250k for each value of n1. Of course, I have an index on each n column. Right now with just the 800k records it can take over a second, sometimes multiple seconds to run the following in order to get a random row from that subset: SELECT COUNT(1) AS total FROM table WHERE n1 = 3; index = random number from 1 to total SELECT data FROM table WHERE n1 = 3 LIMIT index,1; How can I speed this up? I need it to take less than half a second if possible. Thank you.
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Speed Up Query, Order By Column Is Too Slow!
I have a query that takes ages: SELECT tbl1.a, tbl2.b MATCH (tbl1.a) AGAINST ( 'someValue'IN BOOLEAN MODE ) AS score FROM `a` , `b` WHERE tbl2.b = 'someRestriction' ORDER BY score DESC, b.tbl1 DESC LIMIT 20 but because there are thousands of rows it takes ages to do both of the orders, however just : ORDER BY score LIMIT 20 -- is really quick and : ORDER BY b.tbl1 LIMIT 20 -- is really slow is it possible rearrange a constantly updated database so that its naturally ordered by b.tbl1 (so there will be no need to do the ORDER BY b.tbl1 query each time), or are there any other methods to speed this up (putting it all in one table instead of 2, is that significant?)
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Slow SELECT Query INNODB Table
I have a couple hundred connections doing "SELECT [Char36 Field], [LongLong Field], [Long Field] FROM [Connection Specific Table] WHERE [NonIndexed VarChar36 Field]=[Value]". Notice that the table the select statement is being called on is unique to each connection. These tables have less than 10000 records, but this statement can sometimes take over an hour to execute. It is an INNODB table.
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VER VERY VERY Slow MySQL Query HELP URGENTLY NEEDED
I have the following MySQL query, but it is VERY VERY slow and seems to be crashing the server. There are 300,000+ records in the 'tracker' table. SELECT sites.*, SUM(if(tracker.type='view',1,0)) AS numberOfViews, SUM(if(tracker.type='click',1,0)) AS numberOfClicks, SUM(tracker.revenue) AS totalRevenue FROM sites LEFT JOIN tracker ON tracker.site_id = sites.id GROUP BY sites.id ORDER BY sites.domain_name
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Why Does The Slow Query Log Show More Rows Than Exist?
# Time: 070528 17:14:57 # User@Host: counter[counter] @ localhost [] # Query_time: 3 Lock_time: 0 Rows_sent: 7 Rows_examined: 120647 SELECT SQL_CACHE `webpageUrl`, `webpageName`, COUNT(*) AS `count`, (COUNT(*) / (SELECT COUNT(*) FROM _1_log)) AS `pct` FROM _1_log GROUP BY `webpageUrl` ORDER BY `count` DESC LIMIT 7; mysql> select count(*) from _1_log; +----------+ | count(*) | +----------+ | 111824 | +----------+ 1 row in set (0.00 sec)
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TRACKER
