From: scut_tang
Date: June 2 2009 7:11am
Subject: About definition of I_S tables
List-Archive: http://lists.mysql.com/soc/374
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Hi, Sergei.
I found table definition of P_S storage engine is:
There is a directory named performance_schema in var directory, which has lots of .frm files and each stands for one table of P_S.
After perform command "mysql_install_db", performance_schema directory is created.
When user issue a query, like "SELECT * from performance_schema.PROCESSLIST", rnd_init generates table_processlist object and rnd_next gets data. What I want to piont out here is rnd_next uses TABLE *table. The member table of handler contains lots of definitions of opened table. The MySQL server must get all P_S tables definitions from .frm files in performance_schema directory. How can P_S do that? How .frm files can be pre-created? I want I_S to implement like this. I think it works well. It just has some .frm files.
 
Regards
Robin


 
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