Re: newbie to cdb

> Can this database used like mysql?? 

cdb is almost, but not quite, entirely unlike MySQL :-).

cdb provides a hash table.  A hash table maps a key to a value.  In
the case of cdb, both keys and values can be arbitrary binary strings
(even including `\0'), but there is no structure beyond that.

The "db" part of the name comes from analogy with the venerable Unix
libraries such as dbm (which are also hash tables).

The "c" is for "constant": cdb differs from dbm in that, once a cdb
file has been created, it cannot be modified.  (You can, of course,
create a new cdb file containing similar data, perhaps even pulling it
from the old file, although more often there's a "master" text file.
Although this might feel like an update, you're really replacing the
entire table.)

The constant aspect of cdb files avoids a lot of the complications
inherent in dbm (not to mention MySQL!).  This makes cdb ideal for
applications that require very fast lookup of data that doesn't change
very often.  A good example, of course, is mail routing information:
you might change it every day, or every hour, but in the meantime
10000 instances of the mail router have performed lookups.

The Unix password and group files would be ideal candidates for
storing in a cdb file, but I haven't heard that anybody's done that
yet.

Tim.