The RDB$STORAGE_MAP_AREAS system table contains information about
    each storage area to which a storage map refers. The following
    table provides information on the columns of the RDB$STORAGE_MAP_
    AREAS system table.

                                Data
    Column Name                 Type      Summary Description

    RDB$MAP_NAME                char(31)  The name of the storage
                                          map.
    RDB$AREA_NAME               char(31)  The name of the storage
                                          area referred to by the
                                          storage map.
    RDB$ROOT_DBK                char(8)   A pointer to the root of
                                          the SORTED index, if it is
                                          a SORTED index.
    RDB$ORDINAL_POSITION        integer   The order of the storage
                                          area represented by this
                                          row in the map.
    RDB$STORAGE_ID              integer   For a table, a pointer
                                          to the database logical
                                          area. For a hashed index,
                                          a pointer to the system
                                          record.
    RDB$INDEX_ID                integer   A pointer to the index
                                          logical area.
    RDB$STORAGE_BLR             list      The BLR that represents
                                of byte   the SQL clause, WITH LIMIT
                                varying   OF, in the storage map
                                          definition.
    RDB$DESCRIPTION             list      Description of this
                                of byte   partition.
                                varying
    RDB$EXTENSION_PARAMETERS    list      Lists table names and
                                of byte   column names that are
                                varying   referenced by segmented
                                          string storage maps.
    RDB$VERTICAL_PARTITION_     integer   For LIST storage maps,
    INDEX                                 the value indicates the
                                          relationship between areas
                                          of a LIST storage map area
                                          set.
    RDB$FLAGS                   integer   Flags.
    RDB$SECURITY_CLASS          char(20)  Reserved for future use.
    RDB$PARTITION_NAME          char(31)  Name of the index or
                                          storage map partition.