From: Ann W. Harrison
Date: November 4 2008 6:10pm
Subject: Interaction of DDL and DML
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Kevin,

    Currently for both Falcon and InnoDB, a repeatable read
transaction's isolation is broken if a destructive alter table,
drop table, or truncate is executed by a concurrent transaction.

e.g.

T1> select count(*) from t1;
<sees 3>
T2> truncate table t1;
T1> select count(*) from t1;
<sees 0>

When we talked about it, we agreed that we should create a system
of sync objects that prevented a destructive DDL operation from
executing while another transaction was running and had accessed
the table.   That would fix both 40460 and 28006, but it would
make Falcon less compatible with InnoDB.  I have suggested to
Omer that perhaps the Architecture group should weigh in on the
question.

Best,

Ann