c-treeDB and c-tree Plus for .NET bring true relational data management to your application without the overhead of a full SQL implementation yet retain the power and performance of c-tree Plus. c-tree Plus for .NET was designed for ease of use. While intended for new developers to quickly get started c-tree Plus for .NET removes the steep learning curve of the many tedious details of traditional c-tree Plus ISAM handling.
To ensure maximum flexibility and compatibility, c-tree Plus for .NET was designed from the ground up to extend this advanced API to existing c-tree Plus data files! With a simple change of session management mode, you can quickly bring your existing data into the .NET world of fast development.
c-treeDB and c-tree Plus for .NET Sessions and Databases
c-treeDB and c-tree Plus for .NET use the relational concepts of sessions and database to bring advanced functionality to your applications.
c-treeDB and c-tree Plus for .NET Session and Database information are stored in dictionaries. These dictionaries are standard c-tree Plus data files with a defined format.
Sessions essentially log your client application into the c-treeSQL or c-tree Server and provide a collection of databases. For standalone applications, this is still essential such that proper c-tree data structure initialization and manipulation can be done. For instance, transactions and record locking are session-wide activities.
Once a session object is created, you simply log into the session exactly as you would if using the c-tree Server. c-treeDB and c-tree Plus for .NET sessions also have properties and user profile values with respect to traditional c-tree Plus concepts of defining data file and index buffers, file control blocks, sectors (page sizes) and user profiles.
The session dictionary is by default contained in the following file, typically located in the c-tree Server directory, or your application binary for standalone applications:
The session dictionary file layouts are described in the c-tree Plus for .NET Developer’s Guide, Section 3.2.7 “Session Dictionary File Layout”.
c-treeDB and c-tree Plus for .NET databases are collections of tables and indexes (c-tree data and index files) kept in a relational space.
The database dictionary is the database name followed by the .fdd extension. This is also typically located in the c-tree Server directory, or your application binary directory for standalone applications. c-treeSQL also uses this same c-treeDB database dictionary file for relational management. You will find this file in the SQL_SYS directory of the <database>.dbs directory of the c-treeSQL Server.
The database dictionary file layouts are described in the c-tree Plus for .NET Developer’s Guide, Section 3.3.6 “Database Dictionary”.
c-treeDB and c-tree Plus for .NET offer a choice of session management modes. From a c-tree Plus for .NET application you can specify the exact session type to use while working with that session. The following SESSION_TYPE modes are available:
Should you need to do so, you can even change the SESSION_TYPE after you have created a CTSession object. Simply call CTSession.SetSessionType(SESSION_TYPE type), passing the needed SESSION_TYPE.
The following example demonstrates how to log into a c-tree Plus for .NET Session for use with legacy c-tree Plus data and index files, without using the session file nor a database file.
Once a session is established, there is no need to create or manage the session or database dictionary files -- simply go to work with your c-tree Plus data!
If you have a number of tables “organized” in a database and other tables that are not (for example, temporary tables) you can even handle them inside of a single CTSession. Here is an example.
It is possible to change the session mode once logged in. Simply call one of the following methods or functions from c-treeDB or c-tree Plus for .NET. A parameter of TRUE or FALSE can be passed to indicate if this is a “Logon only” type session (CTREE_SESSION).
"The c-tree Bound Server now runs natively in IBM's z/OS mainframe. It uses the Software AG (http://www.softwareag.com) C runtime system for mainframes to allow it to run natively in z/OS, OS/390, VSE/ESA and Siemens BS2000."