View source for Database URL

A database [[URL]] describes a hash database for use with the [[libmu_dbm]] library.  In its full form it has the following syntax:

  scheme://dbfile;params

Of all its parts, only <tt>dbfile</tt> is required.  It specifies the file name (either absolute or relative) of the database file.  If the underlying implementation stores the database in two files (as it is the case with NBDM), <tt>dbfile</tt> will be used as a base name for those files (i.e. the suffixes <tt>.pag</tt> and <tt>.dir</tt> will be appended to it).

If <tt>scheme</tt> is specified, it declares the DBM implementation to use.  Valid values are:

;gdbm
:[http://www.gnu.org/software/gdbm GNU DBM] 
;bdb
:[http://www.oracle.com/technetwork/database/berkeleydb/overview/index.html Berkeley DB]
;ndbm
:Traditional [http://en.wikipedia.org/wiki/Ndbm NDBM]
;tc
:[http://fallabs.com/tokyocabinet/ Tokyo Cabinet]
;kc
:[http://fallabs.com/kyotocabinet Kyoto Cabinet]

In the absense of <tt>scheme</tt> the default database implementation will be used.  This is the first one shown in the list of DBMs when configuring the package.  For example, if <tt>configure</tt> showed:

  Use DBM ....................... GDBM,Berkeley DB v. 4,NDBM

then <tt>gdbm://</tt> will be assumed by default.

<div id="param"></div>
The optional <tt>params</tt> is a list of [[File_Safety_Checks#safety-checks|safety check criteria]], separated by semicolons.  The <tt>default</tt> keyword is synonymous with <tt>all</tt>.
In addition to the usual safety criteria, the following parameter can be used:

;+owner
:Enable the [[File_Safety_Functions#MU_FILE_SAFETY|MU_FILE_SAFETY_OWNER_MISMATCH]] check.  Assume that the database files must be owned by the real UID of the current user.
;owner=''user''
:Enable that check and set the user which must own the database file.  The ''user'' argument is either a valid user name or UID.
;-owner
:Disable that check.

Examples:

  /etc/apop.db
  bdb:///etc/apop.db
  bdb:///etc/apop.db;owner=root;all;-grdfil

[[Category:URL]]