Spam Filter ISP Forums : where 0 = 1 https://www.logsat.com/spamfilter/forums/ Sat, 16 May 2026 01:47:18 +0000 Fri, 18 Jun 2010 00:31:34 +0000 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 11.04 360 https://www.logsat.com/spamfilter/forums/RSS_post_feed.asp?TID=6846 <![CDATA[Spam Filter ISP Forums]]> https://www.logsat.com/spamfilter/forums/forum_images/web_wiz_forums.png https://www.logsat.com/spamfilter/forums/ <![CDATA[where 0 = 1 : So my MyISAM tables were inherited...]]> https://www.logsat.com/spamfilter/forums/forum_posts.asp?TID=6846&PID=13671&title=where-0-1#13671 Author: yapadu
Subject: 6846
Posted: 18 June 2010 at 12:31am

So my MyISAM tables were inherited from before enterprise came out.

I am going to switch to InnoDB and see how it goes with that, since I don't like the table locking when reading.  I do quite a bit of reading from the table to generate reports for users etc.
]]> Fri, 18 Jun 2010 00:31:34 +0000 https://www.logsat.com/spamfilter/forums/forum_posts.asp?TID=6846&PID=13671&title=where-0-1#13671 <![CDATA[where 0 = 1 : The SQl statement:select * from...]]> https://www.logsat.com/spamfilter/forums/forum_posts.asp?TID=6846&PID=13670&title=where-0-1#13670 Author: LogSat
Subject: 6846
Posted: 17 June 2010 at 11:03pm

The SQl statement:
select * from tblmsgs where 0 = 1
is used internally by SpamFilter to return an empty recordset so that rows can then be appended to it, and then added to the database.

In regards to the MyISAM/InnoDB, all the quarantine-related tables are created with MyISAM as it "should" perform better with massive row INSERTs and very few SELECTs. All the tables used by SpamFilter "Enterprise" are InnoDB as they are smaller (by several orders of magnitude) when compared to the quarantine tables, and are used mainly with SELECT statements, and so InnoDB "should" perform better there.

Notice the two "should"s.... At the end, if based on your experience/server load, it's preferable to change the table format to improve performance, you can very well override our recommendations if you notice improvements :-) 
]]> Thu, 17 Jun 2010 23:03:35 +0000 https://www.logsat.com/spamfilter/forums/forum_posts.asp?TID=6846&PID=13670&title=where-0-1#13670 <![CDATA[where 0 = 1 : I have never had database issues...]]> https://www.logsat.com/spamfilter/forums/forum_posts.asp?TID=6846&PID=13668&title=where-0-1#13668 Author: yapadu
Subject: 6846
Posted: 17 June 2010 at 8:46pm

I have never had database issues that I have noticed in the past (too small I guess).  I have been monitoring my situation for a couple of hours, it does not happen all the time but there is some query that is locking the table and seems to take a while to complete. 

I have not tracked down the offending query yet.

I checked my tables and the breakdown is as follows:


tbl_filters            InnoDB
tbl_localdomains        InnoDB
tbl_logindomains        InnoDB
tblbl_attachments        InnoDB
tblbl_countries            InnoDB
tblbl_domains            InnoDB
tblbl_emailfrom            InnoDB
tblbl_emailsto            InnoDB
tblbl_honeypotblockedips    InnoDB
tblbl_honeypotemails        InnoDB
tblbl_ips            InnoDB
tblbl_keywords            InnoDB
tblbl_maps            InnoDB
tblbl_surlbl            InnoDB
tbllogins            InnoDB
tblmsgs                MyISAM    <
tblquarantine            MyISAM    <
tblrejectcodes            MyISAM    <
tblreloadtableinfo        InnoDB
tblservers            MyISAM    <
tblwl_authorizedtoemails    InnoDB
tblwl_autowhitelistforcedeliveryInnoDB
tblwl_domainips            InnoDB
tblwl_emailsfrom        InnoDB
tblwl_eaiilsto            InnoDB
tblwl_keywords            InnoDB

So I have a few MyISAM, but mostly InnoDB.  I checked the database scripts that create the tables, and according to those scripts I should have all InnoDB tables.  I don't know why some of my tables are MyISAM.

So Roberto, did SF on mysql ever use MyISAM or did my tables change in error somehow?

Because of the record locking on InnoDB, vs table locking on MyISAM I would think InnoDB would be the better choice here.

I don't like to make changes to the database on which any software I did not make runs, so I am really amazed those few tables are MyISAM.

Should I change them back Roberto?
]]> Thu, 17 Jun 2010 20:46:13 +0000 https://www.logsat.com/spamfilter/forums/forum_posts.asp?TID=6846&PID=13668&title=where-0-1#13668 <![CDATA[where 0 = 1 : I&#039;ve been fighting database...]]> https://www.logsat.com/spamfilter/forums/forum_posts.asp?TID=6846&PID=13667&title=where-0-1#13667 Author: leeH
Subject: 6846
Posted: 17 June 2010 at 6:40pm

I've been fighting database problems for years now. Today I changed the tables to InnoDB and I have not had one issue since! So far that cured my database issues...
 
Lee
]]> Thu, 17 Jun 2010 18:40:21 +0000 https://www.logsat.com/spamfilter/forums/forum_posts.asp?TID=6846&PID=13667&title=where-0-1#13667 <![CDATA[where 0 = 1 : I am having some database issues...]]> https://www.logsat.com/spamfilter/forums/forum_posts.asp?TID=6846&PID=13666&title=where-0-1#13666 Author: yapadu
Subject: 6846
Posted: 17 June 2010 at 6:15pm

I am having some database issues today, mysql.  When using the thread monitor, I see a lot of locked queries.

Most of them look like this:

select * from tblmsgs where 0 = 1

This seems like a strange query.  I ran the query myself and it is normally quick, but sometimes the database is locked and it takes over 180 seconds.
]]> Thu, 17 Jun 2010 18:15:48 +0000 https://www.logsat.com/spamfilter/forums/forum_posts.asp?TID=6846&PID=13666&title=where-0-1#13666