Common Parameters

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A character string representing the name or IP address of the server where Caché Database is hosted. It can be one of the following formats:

1.   [ localhost ]
2.  [ Server on the Web ]
3.  [ Server on Local Network ]

Please make sure that Caché Database is up and running on the said server before executing any of the connection commands.


A numeric representing the port number on which Caché Database Server is listening to client requests. This number is 1972 by default alloted by the server setup program when Caché Database is installed.

You will never need to change this default port configuration under normal circumstances, though however, you can do so if there is a valid reason to do so. Please refer to Caché reference material to know more about it.


A character string representing user name who is assigned to be connected to the database. On installation Caché creates one user name as _system having all the administrative rights.

You can use default user name or create multiple users with different roles/rights and assign one to the application. Please read the Caché documentation how to manage users.

From CachéRDD point of view a user must have read/write rights to the namespace application is logging to.


A character string representing valid password which is assigned to the <cUserName>. By default Caché assigns SYS as password to _system user at the time of installation.


Amount of time in seconds to wait for the connection to materialize. By default it is 30 seconds.

You should control this parameters through some .ini setting as it may be tweaked under certain circumstances. For all practical purposes default setting holds good.


CachéRDD generated numeric index of the array where information supplied with CachéSetServerParams() and CachéAddConnection(),  or CachéAddConnectionEx() is stored along with the Caché Database returned connection information.

hConnection can be obtained by one of the following three functions:

1. CachéAddConnection()
2. CachéAddConnectionEx()
3. CachéSetConnection()

and is supplied as the last parameter to all the subsequent functions contained in this library.

Please note that RDD funtions affected by hConnection are only DbUseArea() and DbCreate() and corresponding command set. All subsequent RDD calls retrieve this information from AREADATA structure. Thus:


The parameter is OPTIONAL in all affected functions. Amost in all cases default is the return value of CacheSetConnection(), i.e., current active connection. However if you are using more than one connections at the same time, then you may need to supply it to retrieve info from other than current connection.


A character string representing Namespace to connect to. In Caché, NAMESPACE is synonymous to DATABASE in other RDBMS dialects but differs in concept and approach.

One or multiple databses can be mapped to a single Namespace and hence eliminates the need to always point to a physical database which in turn enhances the maintainability of your applications. This parameter is mandatory and assumes no defaults.

A Namespace can not be more than 31 characters in length. For any practical purpose this is sufficient size.