----- Original Message -----
From: "Michael Widenius" <monty@stripped>
To: "Yakov Sudeikin" <yashka@stripped>
Sent: Sunday, August 11, 2002 6:40 PM
Subject: SHOW command - feature request.
> We have on our TODO to extend all SHOW columns to have support for
> specifying which columns you want to return, expressions on these, the
> WHERE clause and ORDER BY.
> We have not 100 % agreed on the syntax for these, but it will be
> specified before we start to implement this in 4.1 or 5.0. We
> probably will both support 'virtual tables' for the different SHOW
> command and extended SHOW syntax. (The later because it will be much
> easier to remember).
My own opinion is to have just virtual tables. With ones it will be possible to
specify any WHERE expression and order direction.
> Yakov> CREATE TABLE filesystem (dir flag, root_r flag, root_w flag, root_r
flag, group_r flag, group_w flag, group_x flag, other_r flag, other_w flag,
> Yakov> FLAG is something alike BOOLEAN. But all flags are gouped that way that
1 to 8 flags will occupy only one byte. up to 32 flags will occupy up to 4
bytes. The flag also may have a possibility to represent more that two
conditions. For instance:
> Yakov> CREATE TABLE orders (......., order_status flag(4), order_importance
> Yakov> 4 and 6 in example above represent the number of possible conditions of
the flag. The order_status flag will occupy 2 bits, and order_importance will
occupy 3 bits. They together will fit into one byte.
> Yakov> With this ability MySQL will be able to save us a lot of disc and
> Our plan is to instead support add in 4.1 support for the BIT type,
> which will make things like this possible:
> CREATE TABLE orders (......., order_status bit(4), order_importance bit(6));
Michael, did you mean
CREATE TABLE orders (......., order_status bit(2), order_importance bit(3));
(Yakov means a number in () specifies number of diffirent values of field, not
its length in bits).