Delphi

Question:
What is the role of DBClient.DLL?

Answer:
DBCLIENT.DLL contains the low-level implementation of
TClientDataSet. It manages all of the data and implements
functionality like filters, sorting, etc. The relationship
between TClientDataSet and DBCLIENT.DLL is very similar to the
one between TTable and the BDE. The functionality is surfaced

through two COM interfaces (DSBase & DSCursor) and requires OLE
registration. If DBCLIENT.DLL is placed in any directory on the
path or in the EXE directory on the client machine, it will
automatically be registered by the VCL code in TClientDataSet.
Otherwise it must be registered using REGSVR32.EXE or TREGSVR.EXE.