Commands Not to Be Called within a Transaction
Following is a list of commands that return an error if executed while a transaction is in progress:
open
close
login
logout
zerofile
All actions that change the structure of a table, such as adding or deleting columns, should not be done within a transaction. The following is a list of such commands that should not be executed within a transaction (but will not return an error):
create_field
create_index
delete_field
delete_index
erasefile
sort
structure_abort
structure_copy
structure_end
structure_start