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DBCREATE

DBCREATE

Name


      DBCREATE

Purpose


      Create a new data base (.dbf), index (.dbx) or description (.dbh) file

Explanation


      A database definition (.dbd) file must already exist in the current
      directory or in a ZDBASE directory. The new .dbf, .dbx and/or .dbh
      files will be written to the same directory. So if the .dbd file is
      in a ZDBASE directory, then the user must have write privilege to that
      directory
      This version allows record length to be larger than 32767 bytes

Calling Sequence


      dbcreate, name,[ newindex, newdb, maxitems] [,/EXTERNAL, MAXENTRY=]

Inputs


      name- name of the data base (with no qualifier), scalar string.
              The description will be read from the file "NAME".dbd
              Maximum length of name is 19 characters.

Optional Inputs


      newindex - if non-zero then a new index file is created,
              otherwise it is assumed that changes do not affect the
              index file. (default=0)
      newdb - if non-zero then a new data base file (.dbf) will
              be created. Otherwise changes are assumed not to affect
              the file's present format.
      maxitems - maximum number of items in data base.
              If not supplied then the number of items is
              limited to 1000.

Outputs


      NONE.

Optional Input Keywords



      external - If set, then the database is written with an external data
              representation. This allows the database files to be used on
              any computer platform, e.g. through NFS mounts, but some
              overhead is added to reading the files. The default is to
              write the data in the native format of the computer being used.
              This keyword is only paid attention to if NEWDB or NEWINDEX
              are nonzero. Otherwise, the database is opened to find
              out if it uses external representation or not.
              Extreme caution should be used if this keyword is used with
              only NEWINDEX set to a nonzero value. This mode is allowed so
              that databases written on machines which already use the
              external data representation format, e.g. Sun workstations, to
              be marked external so that other machines can read them.
      MAXENTRY - positive integer giving the maximum number of entries in the
              database (needed to adjust the size of the index file). This
              keyword can be used to supercede the #maxentries line in the
              .dbd file (the larger of the two numbers will be used).

Procedure Calls


      GETTOK(), FIND_WITH_DEF(), ZPARCHECK

Restrictions


      If newdb=0 is not specified, the changes to the .dbd file can
      not alter the length of the records in the data base file.
      and may not alter positions of current fields in the file.
      permissible changes are:
              1) utilization of spares to create a item or field
              2) change in field name(s)
              3) respecification of index items
              4) changes in default print formats
              5) change in data base title
              6) changes in pointer specification to other data
                      data bases
      !priv must be 2 or greater to execute this routine.

Side Effects


      data base description file ZDBASE:name.dbh is created
      and optionally ZDBASE:name.dbf (data file) and
      ZDBASE.dbx (index file) if it is a new data base.

Revision History


      D. Lindler, GSFC/HRS, October 1987
      Modified: Version 1, William Thompson, GSFC, 29 March 1994
                  Version 2, William Thompson, GSFC/CDS (ARC), 28 May 1994
                  Added EXTERNAL keyword.
      Version 4, William Thompson, GSFC, 3 November 1994
                      Modified to allow ZDBASE to be a path string.
      8/14/95 JKF/ACC - allow EXTERNAL data for newindex OR newdb modes.
      Make sure all databases closed before starting W. Landsman June 1997
      Added new unsigned and 64 bit integer datatypes W. Landsman July 2001
      Make sure to use lowercase filenames on Unix W. Landsman May 2006
      Added MAXENTRY keyword W. Landsman July 2006
      Assume since V5.5, remove obsolete keywords to OPEN W. Landsman Sep2006
      No longer required to be a ZDBASE directory W. Landsman Feb 2008
      Fix Feb 2008 bug when files are in current dir W. L. May 2008
      Fix May 2008 bug when files are not in current dir (sigh) W. L. May 2008
      Warn if database length exceeds 32767 bytes W.L. Dec 2009
      Remove spurious warning that database name is too long W.L. April 2010
      Support entry lengths larger than 32767 bytes W.L. Oct. 2010
      Better testing for valid print formats W.L. Nov 2010
      Fix problem where descriptions of different items could overlap
            E.Shaya/W.L. Oct. 2012
      Work better when .db files are not in current directory W.L. Oct 2013
      Maxitems now defaults to 1000 W.L. Jan 2015



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