TABLE/KEY RELATIONS

Problem:

When there are many tables, linked together through the foreign key
constraints, then loading one table will recursively open other tables.  This
can sometimes lead to thread stack overflow.  In such situations the server
will exit.

I see the stack overflow problem when the thread_stack is 196608 (the default
value for 32-bit systems).  I don't see the problem when the thread_stack is
set to 262144 (the default value for 64-bit systems).

Solution:

Currently, in InnoDB, there is a macro DICT_FK_MAX_RECURSIVE_LOAD which defines
the maximum number of tables that will be loaded recursively because of foreign
key relations.  This is currently set to 250.  We can reduce this number to 33
(anything more than 33 does not solve the problem for the default value).  We
can keep it small enough so that thread stack overflow does not happen for the
default values.  Reducing the DICT_FK_MAX_RECURSIVE_LOAD will not affect the
functionality of InnoDB.  The tables will eventually be loaded. 

rb#2058 approved by Marko