ADO vs. BDE

[StevenK]

I'm curious to know the advantages/disadvantages between making use of ADO components and BDE components (standard TTable + TQuery components and the like).
I understand by using the appropriate ADO components you then no longer need to install the BDE on client machines. Someone also suggested that ADO data access is quicker.
Can anyone shed any light on this ?
I'm using Delphi 5 and my back end database is SQL Server 7.0.
Thanks in advance.
Steve

 

[svanels]

ActiveX Data Objects (ADO) and Borland Database Engine (BDE) have the same funcionality. It is a bridge between the database representation in Delphi, and the physical database.
Both consist of a bunch of dll's and api's which take care of the communication on both sides.

Advantages of ADO: In Windows ME and Windows 2000 in most cases it is installed together with the operating system.

Disadvantage: On Windows NT, 95 and 98, you have to Install it yourself

This is section of

http://delphi.about.com/library/weekly/aa022001c.htm

To access any kind of database with ADO, you'll of course need to have ADO/OLE DB libraries. Everything you need to use ADO is probably already on your computer: the files are distributed by Microsoft as a part of Windows 98/2000. If you or your client use Windows 95 or Windows NT you will probably need to distribute and install the ADO engine. Delphi 5's CD includes an installation of MDAC - Microsoft Data Access Components. You should always make sure to have the latest version, which is available from Microsoft. The Microsoft Data Access Components are the key technologies that enable Universal Data Access. They include ActiveX Data Objects (ADO), OLE DB, and Open Database Connectivity (ODBC).
Note: to install correctly on a Windows 95 computer, MDAC requires that DCOM95 be installed. MDAC installs components that rely on DLLs installed by DCOM95 in order to register correctly. Note that DCOM95 is not required on a Windows NT 4.0. In some cases, DCOM may not be installed on a Windows 98 computer. If it has not been installed, then DCOM98 should be installed prior to the installation of MDAC
end of section

About that ADO quicker is I do not know, can be, but In my opinion depends on your programming habbits.

I would compare ADO with the IBX components which are only designed to work with Interbase.

The big advantage of the BDE from a developpers point of view: It is database independent.

In terms of Client server systems.

Lets say you make Inventory Management System. You start with Interbase, use TTable, TQuery, TStoredProcedure, enfim the standard BDE components.
If your client wants Oracle or SQL server, you make the same tables etc. in Oracle or SQL Server. With the Datapump utility this can be done automatically.
With the BDE administrator you modify the alias to point to the other RDBMS, and you are in bussiness, of course I suspect that you will have some minor sintaxe modifications in your queries with parameters.

But if you use ADO or IBX, to shift to Oracle you must in the most favorable case redesign completely your datamodules.

I would stick by the BDE

Regards








S. van Els
SAvanEls@cq-link.sr