Question - If you run this, what does it return?
select applock_mode('public', 'SalesApp', 'Transaction')
Answer -
The type of lock being held by an application that requested it.
This command returns the lock mode held by an application that was requested with the sp_getapplock procedure.
insert mytable select ''
insert mytable select ' '
select * from mytable where mychar = ''
select * from mytable where mychar = ' '