You connect to Advantage from PHP by calling the function ads_connect. This function takes either three or four arguments and returns a connection resource. The first argument is an ODBC connection string. The PHP driver connects through the ODBC API by invoking SQLDriverConnect, to which it passes this connection string. See Table 19-1 for the required and valid connection string parameters.

The second and third parameters are the user name and password to use for the connection, and the optional fourth parameter is used to define what type of cursor you want returned. The valid values for this fourth parameter are:

•        0 (SQL_CURSOR_FORWARD_ONLY)

If you omit this parameter, a live (dynamic) cursor is returned.

The following is an example of a call to ads_connect:

$rConn = ads_connect("DataDirectory=\\\\server\\share\\".
 "adsbook\\DemoDictionary.add;ServerTypes=2;",
 "adsuser", "password");

The connection string in this command attempts to connect to the DemoDictionary data dictionary located on a share named share on a server named server. In addition, this connection string specifies that it wants to connect to ADS (the license for ALS does not permit you to connect to ALS from a Web server). As is the case with ODBC connections, all parameters not included in the connection string will be expanded using the default parameter values.

Once you are through with the connection, you must close it. You do this by invoking ads_close, passing the connection resource obtained from the call to ads_connect. The following is a simple example of this function call:

ads_close( $rConn );