🚀 go-pugleaf

I am doing two-tier database application by C++ Builder 5.0 with MS Access
2000 and MS SQL server by ODBC.

The question I have is if two or more instances of my database application
from different machines try to access the same table of the database, only
one of them is allowed to modify the data, others just can read data. Is
there a mechanism to handle such situation. I understand that when the
applications try to access the database, a connection is setup for each
application with the database. Is there a way that before a application
accesses to the database, it check the connection of the database, if there
is more that one connection with the database, the application just allows
its Data Controls Components to read the data; After the application which
could modify the data (i.e. first application accesses to the database)
closes or crashes, it release its connection with database, then the other
application could access to the database and modify the data?

Thank you!