Deletes all but the highest version of specified dictionary
       objects.

       Format

                [ path-name  [,...] ]
         PURGE  [ ALL               ]  [KEEP  [=]  n]
                [                   ]

1  –  Arguments

    path-name

       Specifies the object you want to purge. The path name must
       include the name of a domain, record, procedure, or table. The
       path name cannot contain a version number or a semicolon. If you
       do not specify a path name, DEC DATATRIEVE purges all objects in
       your default dictionary directory. PURGE accepts both DMU and CDO
       style path names.

    ALL

       Purges all the definitions in the default dictionary directory.
       ALL is the default.

    KEEP [=] n

       Specifies the number of versions of each object you want to keep.
       The number must be greater than zero. The default is KEEP=1.

2  –  Examples

       The following example shows how PURGE deletes all but the highest
       versions of objects in a user's DMU format directory:

       DTR> SHOW ALL
       Domains:
         * FAMILIES;3  * FAMILIES;2   * FAMILIES;1   * OWNERS;2
         * OWNERS;1    * PETS;2       * PETS;1       * PROJECTS;3
         * PROJECTS;2  * PROJECTS;1   * YACHTS;5     * YACHTS;4

       Records:
         * FAMILY_REC;2 * FAMILY_REC;1 * OWNER_RECORD;2 * OWNER_RECORD;1
         * PET_REC;1    * PROJECT_REC;1 * YACHT;2       * YACHT;1

       The default directory is CDD$TOP.DTR$USERS.BELL
       No established collections.
       No ready sources.
       No loaded tables.
       DTR> PURGE
       DTR> SHOW DOMAINS, RECORDS
       Domains:
         * FAMILIES;3   * OWNERS;2     * PETS;2      * PROJECTS;3
         * YACHTS;5
       Records:
         * FAMILY_REC;2 * OWNER_RECORD;2 * PET_REC;1 * PROJECT_REC;1
         * YACHT;2

       DTR>

       The following example shows the error message generated if you
       specify a dictionary directory as the final object in the path
       name. It then shows how PURGE works with the path name and KEEP
       arguments.

       DTR> SHOW DICTIONARY
       The default directory is CDD$TOP.DTR$USERS.BELL

       DTR> PURGE CDD$TOP.DTR$USERS.BELL
       Element "CDD$TOP.DTR$USERS.BELL" is not a Domain, Record, Procedure,
        or Table.
       No objects purged for dictionary element "CDD$TOP.DTR$USERS.BELL".

       DTR> SHOW RECORDS

       Records:
         * FAMILY_REC;4   * FAMILY_REC;3   * FAMILY_REC;2 * FAMILY_REC;1
         * OWNER_RECORD;2 * OWNER_RECORD;1 * PET_REC;1    * PROJECT_REC;1
         * YACHT;2        * YACHT;1

       DTR> PURGE CDD$TOP.DTR$USERS.BELL.FAMILY_REC KEEP=2
       DTR> SHOW RECORDS
       Records:
         * FAMILY_REC;4 * FAMILY_REC;3  * OWNER_RECORD;2 * OWNER_RECORD;1
         * PET_REC;1    * PROJECT_REC;1 * YACHT;2        * YACHT;1

       DTR>