set but is ignored".
This patch makes @@session.max_allowed_packed and
@@session.net_buffer_length read-only as suggested in the bug
report. The user will have to use SET GLOBAL (and reconnect)
to alter the session values of these variables.
The error string ER_VARIABLE_IS_READONLY is introduced.
Tests are modified accordingly.
sql/set_var.cc:
The class sys_var_thd_ulong_session_readonly is introduced as
a specialization of sys_var_thd_ulong implementing a read-only
session variable. The class overrides check() and
check_default() to achieve the read-only property for the
session part of the variable.
sql/set_var.h:
The class sys_var_thd_ulong_session_readonly is introduced as
a specialization of sys_var_thd_ulong implementing a read-only
session variable. The class overrides check() and
check_default() to achieve the read-only property for the
session part of the variable.
sql/share/errmsg.txt:
New error ER_VARIABLE_IS_READONLY.
