alter merge table doesn't work as documented (?)

["Jim Lyons" <jlyons4435@xxxxxxxxx>]

I have a merge table and dropped one of the tables that was in the union.  I
then tried to alter the merge table to use only the remaining tables.

Here is some simple test code representing what I was doing.

########################
create table t1 (x int);
create table t2 (x int);
create table t3 (x int);

create table t_merge (x int) engine=merge union=(t1,t2,t3);

drop table t1;

alter table t_merge union=(t2, t3);
##########################

As I read the doc, this ought to work, leaving me with a merge table with
only 2 tables in the union.  The output I got was (the error message is at
the end):

--------------
create table t1 (x int)
--------------

--------------
create table t2 (x int)
--------------

--------------
create table t3 (x int)
--------------

--------------
create table t_merge (x int) engine=merge union=(t1,t2,t3)
--------------

--------------
drop table t1
--------------

--------------
alter table t_merge union=(t2, t3)
--------------

ERROR 1146 (42S02) at line 16: Table 'jlyons.t1' doesn't exist

Is this a bug or expected behavior?

Thanks,
Jim

-- 
Jim Lyons
Web developer / Database administrator
http://www.weblyons.com