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At the top of BDE's locking hierarchy is the session layer. The session indirectly controls some locks because it controls resources including database handles and table cursors. Multiple database handles can be opened in the same session; this is what gives the application access to different databases at the same time. When a session is closed, all resources attached to the session are closed and all locks owned by those resources are released.

The session directly owns table locks and record locks acquired by an application after the table has been opened. This means that if more than one cursor is open on the same table within a session, one cursor can release a lock that was acquired by another cursor. Sessions provide complete isolation from each other.