On Jun 01, scut_tang wrote:
> KEY ACCOMPLISHMENTS LAST WEEK
> More clear about the old and new implementation of I_S.
> Extend the part of old implementation of wiki.
> Push the code to:
> But it is just a skeleton, renamed from example storage engine.
No, it's not pushed.
Looking at https://launchpad.net/~scut-tang/mysql-server/mysql-6.0-infoschema
I see "Recent revisions: This branch has not been pushed to yet."
That is, you've created a branch on launchpad, but haven't pushed the
source code there yet.
> KEY GOOD VIBRATIONS
> Think about new implementation of Sergei's idea and have a blueprint
> in my mind, which will write into wiki.
> KEY CONCERNS
> 1. Does the I_S storage engine support write/update? For what
> situation? I think all I_S table would be readonly.
You can start from readonly tables, but eventually we need to support
updates too. Certain P_S tables are writable.
> 2. What does the table descriptor in the wiki mean? Is it a new one or
> TABLE struture?
A structure that "describes" a table. Currently a pair of structures
ST_SCHEMA_TABLE and ST_FIELD_INFO describe the table. You implementation
will have something similar.
> 3. I want to define I_S table like the old implementation, which has
> field definition and some callbacks. Does it work?
Absolutely. That's how it should be done.
> And how is the index definition?
Something similar. struct ST_INDEX_INFO perhaps ?
> 4. You said it is good for a clear API for I_S plugins, separate from
> server internals. But I think there must be some special for I_S
> storage engine. Because before "SELECT * FROM database.table", "USE
> database" must perform. So user must perform "USE INFORMATION_SCHEMA"
> before a query of I_S table, and this is not like the current style.
Arjen already replied to that.
> 5. Will perfschema storage engine formally enter into MySQL code base
> in the future? I saw some storage engines in mysql-6.0-perfschema have
> some variables about perfschema. My source code is based on
Yes, it will.
What engines have what variables ?
Regards / Mit vielen Grüßen,
__ ___ ___ ____ __
/ |/ /_ __/ __/ __ \/ / Sergei Golubchik <serg@stripped>
/ /|_/ / // /\ \/ /_/ / /__ Principal Software Engineer/Server Architect
/_/ /_/\_, /___/\___\_\___/ Sun Microsystems GmbH, HRB München 161028
<___/ Sonnenallee 1, 85551 Kirchheim-Heimstetten
Geschäftsführer: Thomas Schroeder, Wolfgang Engels, Wolf Frenkel
Vorsitzender des Aufsichtsrates: Martin Häring