NetMaster Database Administration › Delete an NDB › Delete All Data in an NDB

Delete All Data in an NDB

If an NDB is being used as a journal file (that is, it is cleared regularly after a specified time or number of records, for example), it can be cleared in three ways:

• Write an NCL procedure that reads the entire database sequentially (for example, by RID) and deletes all records-this method is slow and tedious.
• Physically delete the data set (or issue a UDBCTL OPEN RESET command if the data set is defined with REUSE), and re-create it, as described previously-this method has practical uses, such as when the data set must be relocated on DASD or needs more space.
• Use the NDB RESET command-this method is normally the best approach.

  The NDB RESET command deletes all data records (and their keys) from an NDB, but preserves the field definitions. Thus, it is equivalent to deleting, defining, re-creating, and reissuing all &NDBDEF ADD statements or NDB FIELD commands required to build the field definitions.

  An NDB must not be active when the NDB RESET command is issued. This prevents active users from having the database cleared underneath them. A LOCKED database cannot be reset.

  The following sequence of commands resets an NDB:

  NDB STOP dbname IMM
  

  NDB RESET dbname
  

  If the database is not active, then the NDB STOP command effectively does nothing. The RESET command gives you the option of placing the database into LOAD MODE.