Creating the WRT file

Note: Compression of Sybase databases is implemented by supported versions Sybase Adaptive Server Anywhere 6, 7 and 9. In version Sybase SQL Anywhere 12 the utility for database compression does not exist and this feature is considered to be obsolete. Depository databases in Sybase SQL Anywhere 12 are ordinary Sybase databases (files .db a .log). Therefore this whole section is relevant to Sybase Adaptive Server Anywhere versions 6, 7 and 9 only.

The process D2000 Archiv (if it is necessary (defined)) continuously creates depository database with the suffix *.cdb. It is a compressed database, that is available by means of so-called Write file with the suffix *.wrt. This file may be created as follows:

  1. Run the program Sybase Central using the start menu.
  2. Select Utilities
    3. option in the left window.
  3. Select Create Write File option in the right window.
  4. Then in successive steps:
    1. Select the particular *.cbd file (depository database).
    2. Confirm other offered settings.

This procedure will create the particular *.wrt file in the directory, where the selected *.cdb file is located. Location of the *.wrt file may be changed (it is necessary, if the depositories are saved on a read-only data medium).

Creating a *.wrt file may be also started from the command line using the program dbwrite.exe (it is copied on the disk during the installation of the database server Sybase).

C:\Sybase60\Adaptive Server Anywhere 6.0\win32>dbwrite
 Usage: dbwrite [switches] database [write-file-name]
 Switches (use specified lower-case letter, as shown):
-c create a new write file
 -d make existing write file point to another database
 -f filename force write file to point at filename
 -m <name> set transaction log mirror name (only with -c)
 -o <file> log output messages to file
 -q quiet: do not print messages
 -s status of existing write file (default)
 -t <name> set transaction log name (only with -c)
 -y erase old file(s) without confirmation

Example:

dbwrite -c trezor.cdb

or

dbwrite -c trezor.cdb c:\trezor.cdb
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