The communications database

CommDb is the communications database server. This server provides access to an (extensible) database which holds information about internet access, connection preferences, GPRS connections, modems, locations, charge-cards, location information, WAP settings, and proxy servers.

The database provides a single repository of communications related information which all communications type software components and applications can access.

The information is held in the form of individual tables within a single database managed by CommDb. The classes provided by CommDb use DBMS in their implementation and it is DBMS which provides the underlying behaviour for handling the database itself. In effect, CommDb is a layer over DBMS.

CommDb allows multiple clients to access concurrently the tables within the communications database. The locking mechanism of the underlying DBMS allows concurrent access by multiple clients while safeguarding the integrity of the database for changes.

Version 6.0 of CommDb allowed clients the option of two different database structures: termed IAP- and ISP-type databases respectively. IAP (Internet Access Point)-type databases provides an IAP table that allows an ISP record and a chargecard to be identified as a group. An ISP-type database does not have an IAP table, but is otherwise identical.

For Version 6.1, the use of ISP-type databases is deprecated.

Major changes between Versions 6.0 and 6.1 are as follows:

• New support for storing information relating to connecting through GPRS. See Incoming and Outgoing GPRS tables.

• The DIAL_OUT_IAP and DIAL_IN_IAP tables have been united into a single IAP table.

• The Global table no longer stores information about a default connection. Instead, a Connection preferences table is provided that stores connection options ranked by preference. This global setting for whether to prompt the user to choose a service before dialling is also replaced by a setting for dialog preference in the Connection preference table.

For detailed version information, see the CommDb API Reference.

Despite the table changes between Versions 6.0 and 6.1, the CommDb API still supports clients written to use Version 6.0. In particular, note the following:

• Calls that use the old IAP tables are translated to use the new IAP table.

• Calls that use the old Global table are translated to use the Connection preferences table. For details, see the documentation for CCommsDatabase::SetGlobalSettingL() and CCommsDatabase::GetGlobalSettingL().