In addition to normal ODBC support, the Unified ODBC functions in PHP allow you to access several databases that have borrowed the semantics of the ODBC API to implement their own API. Instead of maintaining multiple database drivers that were all nearly identical, these drivers have been unified into a single set of ODBC functions.

Libmcal is a C library for accessing calendars. It's written to be very modular, with pluggable drivers. MCAL is the calendar equivalent of the IMAP module for mailboxes.

The connection id returned by this functions is needed by other ODBC functions. You can have multiple connections open at once. The optional fourth parameter sets the type of cursor to be used for this connection. This parameter is not normally needed, but can be useful for working around problems with some ODBC drivers.

This function allows fiddling with the ODBC options for a particular connection or query result. It was written to help find work arounds to problems in quirky ODBC drivers. You should probably only use this function if you are an ODBC programmer and understand the effects the various options will have. You will certainly need a good ODBC reference to explain all the different options and values that can be used. Different driver versions support different options.

ע There is no ODBC involved when connecting to the above databases. The functions that you use to speak natively to them just happen to share the same names and syntax as the ODBC functions. The exception to this is iODBC. Building PHP with iODBC support enables you to use any ODBC compliant drivers with your PHP applications. iODBC is maintained by OpenLink Software. More information on iODBC, as well as a HOWTO, is available at www.iodbc.org.