🚀 go-pugleaf

I'm new to SQL, and I haven't seen any reference to record locking. How
can I achieve record locking and how would I verify that a record is
locked before use ?

I'm currently using:

select 1
use customer order cname
>>>> search routine & selection

if rlock()
    msgbox('Record currently being edited...')
else
    >>> editing routine of customer record
    unlock
endif

please forgive the crudeness, but how would I implement this into a SQL
environment ?

TIA
Jeff