The dbm database-map type, which is really the ndbm form of database, is the traditional form of Unix database file. Data is stored in one file, keys in another. The data must fit in blocks of fixed sizes, so there is usually a limit on the maximum size (1 kilobyte or so) on any given stored piece of data. The dbm database-map type is available only if sendmail was compiled with NDBM declared (NDBM). Many database switches are available with this dbm database-map type. All are listed in Table 23-9. Table 23-9. The dbm database-map type K command switches
This is the database-map type used with aliases files, if the hash type is unavailable. This type is also needed on machines that employ NIS because the underlying files for those services are stored in dbm format. Note that because of the implicit limit on the size of a piece of data, you should consider using one of the db (3) hash or btree types instead. |