dbExpress Drivers Frequently Asked Questions

If you have purchased a full version of a driver, you are entitled to distribute the driver with pre-compiled programs created with its use. You are not entitled to sell any components or libraries inherited from the driver or using its source code. For more information see the License.rtf file in the installation directory of the driver.

After DbxOda 4.00, DbxSda 4.00, DbxMda 4.00, DbxIda 2.00, and for DbxPgSql all upgrades to future versions are free to users with an active Subscription.

Users that have a registration for previous versions of a driver will have to first upgrade to jump in on the Subscription program.

The Subscription Program is an annual maintenance and support service for users of Devart dbExpress drivers.

Users with a valid Subscription get the following benefits:

• Access to new versions of the driver when they are released
• Access to all updates and bug fixes of the driver
• Product support through the Priority Support program
• Notification of new product versions

Priority Support is an advanced product support program which offers you expedited individual assistance with product-related questions from the developers themselves. Priority Support is carried out over email and has a two business day response policy.

The Subscription Program is available for registered users of DbxOda 4.00, DbxSda 4.00, DbxMda 4.00, DbxIda 2.00, DbxPgSql 1.00 and higher.

Yes, you can. Driver version licenses are perpetual.

An annual driver Subscription is included when ordering or upgrading to any registered (non-Trial) edition of DbxOda 4.00, DbxSda 4.00, DbxMda 4.00, DbxIda 2.00, DbxPgSql 1.00 or higher.

You can renew your driver Subscription on the Ordering Page. For more information, please contact sales@devart.com.

To upgrade to DbxOda 4.00, DbxSda 4.00, DbxMda 4.00, DbxIda 2.00, you can get a Version Update from the Ordering Page. For more information, please contact sales@devart.com.

Firstly you should take care of the driver itself to be presented on the client computer. Other items depend on the driver you are using:

DbxOda: You do not need any additional files if the driver works in Direct mode. Otherwise, you should install the Oracle client.

DbxSda: You should have OLE DB provider installed on the client. In current versions of Microsoft Windows, as Windows 2000, OLE DB is already included. But it is highly recommended to download latest version of Microsoft Data Access Components (MDAC) at http://www.microsoft.com/data.
If you work with SQL Server Compact Edition, the server itself should be installed on the client computer.

DbxMda: Generally you do not need any additional files to be installed. Below you can see the only exceptions:

• If you use MySQL Embedded server, you need the server itself (libmysqld.dll) and accompanying files like errmsg.sys.
• If you use the "MySQL (Devart)" driver that uses MySQL client, you need the client library (libmysql.dll).

DbxIda: You should install the InterBase or Firebird client.

DbxPgSql: You do not need any additional files.

dbExpress technology serves for providing a more or less uniform way to access different servers (Oracle, SQL Server, MySQL, and so on). It is based on drivers that include server-specific features. Like any universal tool, in many specialized cases dbExpress providers lose some functionality. For example, the dbExpress design-time is quite poor and cannot be expanded.

Our Data Access Components (DACs) are specialized sets of components for specific servers, which have advanced server-specific design-time editors, and a component interface similar to that of BDE.

We tried to include maximal support of server-specific features in both dbExpress drivers and DACs. However, the nature of dbExpress technology has some restrictions that cannot be overcome.

DACs and dbExpress drivers use the same kernel and thus have similar performance. In some cases dbExpress is slower because data undergoes additional conversion to correspond to dbExpress standards.

To summarise, if it is important for you to be able to quickly adapt your application to different database servers, it is probably better to use dbExpress drivers. In other cases, especially when migrating from BDE or ADO, you should use DACs. There are several dll files in the installation directory of the driver. Which one should I use in my application?

It depends on the version of your IDE:

• With Delphi 2007 and C++Builder 2007 you should use the dbexpXda40.dll file.
• With BDS 2006 and Turbos you should use the dbexpXda30.dll file.
• With other IDE you should use dbexpXda.dll.

DbxMda, DbxPgSql: You can set the port number in two ways:

• after the server name delimited by colon:

  SQLConnection.Params.Add('HostName=MyServer:3307');

• using the 'Server Port' parameter:

  SQLConnection.Params.Add('Server Port=3307');

  This way works for Delph 7 and higher IDE versions.

DbxIda: You can set the port number in the Database parameter using the following format: HostName/Port:DBPath