Hi,
it means, if you you want to update the table, so you have to lock it, and nobody can update only you,
there is a lock object "E_TABLE" to lock any table in SAP, so just look at this below url it could help you,...
by the way, you can create a lock object by using this transaction SE11, and every lock object should be started with "E"
and there are 2 functions FM, to lock the table and unlock it,
ENQUEUE_E_TABLE
ENQUEUE_E_TABLE
http://searchsap.techtarget.com/tip/Locking-and-unlocking-of-tables
Regards
Ibr