Three directories are used when establishing or setting up a new database.
A local database directory file exists in each path (called a "drive" on some operating systems) in which a database has been defined. This directory contains one entry for each database accessible from that location. Each entry contains:
To see the contents of this file for a particular database, issue the following command, where location specifies the location of the database:
LIST DATABASE DIRECTORY ON location
A system database directory file exists for each instance of the database manager, and contains one entry for each database that has been cataloged for this instance. Databases are implicitly cataloged when the CREATE DATABASE command is issued and can also be explicitly cataloged with the CATALOG DATABASE command. For information about cataloging databases, see Cataloging a Database.
For each database created, an entry is added to the directory containing the following information:
To see the contents of this file, issue the LIST DATABASE DIRECTORY command without specifying the location of the database directory file.
In a partitioned database environment, you must ensure that all database partitions always access the same system database directory file, sqldbdir, in the sqldbdir subdirectory of the home directory for the instance. Unpredictable errors can occur if either the system database directory or the system intention file sqldbins in the same sqldbdir subdirectory are symbolic links to another file that is on a shared file system. These files are described in Enabling Data Partitioning.
The database manager creates the node directory when the first database partition is cataloged. To catalog a database partition, use the CATALOG NODE command. To list the contents of the local node directory, use the LIST NODE DIRECTORY command. The node directory is created and maintained on each database client. The directory contains an entry for each remote workstation having one or more databases that the client can access. The DB2 client uses the communication end point information in the node directory whenever a database connection or instance attachment is requested.
The entries in the directory also contain information on the type of communication protocol to be used to communicate from the client to the remote database partition. Cataloging a local database partition creates an alias for an instance that resides on the same machine. A local node should be cataloged when there is more than one instance on the same workstation to be accessed from the user's client.