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Transaction Log Format

c-treeACE V9 introduces a change in the transaction log format to accommodate new capabilities. While FairCom always attempts to maintain backward compatibility whenever possible, transaction logs from earlier versions of c-tree will be incompatible with the new c-treeACE format.

Note: Your existing data and index files are not affected by this change, only any existing transaction logs (for example, files such as L0000001.FCS).

It is easy to install and use c-treeACE with your existing files. Simply remove the old transaction logs in a safe manner. Follow these easy steps, which are appropriate any time you are upgrading a c-tree installation.

  1. Have all clients cleanly exit from the existing c-tree Server.
  2. Perform a normal controlled shutdown of the c-tree Server using one of the methods described here, depending upon your server installation:
    • Server Console Window - From the c-tree Server console window click “Control” and then click “Shutdown the c-tree(SQL) Server”
    • Windows Toolbar - Right-click the c-tree Server icon in the Windows Tooltray and choose “ShutDown the c-tree Server”
    • Windows Service - From the Windows Control Panel, choose “Administrative Tools”, then choose “Services”. Locate the FairCom c-tree Server in the list of services running on your machine. Right-click the c-tree Service and choose “Stop”.
    • Use the client command line utility, ctadmn, and follow the prompts.
    • Use the client command line utility, ctstop.
  3. Block the ability of any clients to attach to the c-tree Server.
  4. Restart the existing c-tree Server with no clients attached and allow a successful automatic recovery to take place. This ensures all files are brought to a consistent state in the event there is any data remaining in the transaction logs.
  5. Perform another normal controlled shutdown of the c-tree Server.
  6. Remove all existing transaction logs and associated files (L*.FCS, S*.FCS, D*.FCS and I*.FCS).
  7. Copy the c-treeACE executable (ctsrvr.exe or ctreesql.exe) into the existing c-tree Server directory.

    Note: Only V9 clients can connect to the new c-treeACE database engine.

  8. Unblock the ability of any clients to attach.
  9. Start c-treeACE in your usual manner and begin using your existing data.

FairCom has added logic to c-treeACE attempting to notify you where transaction logs may be incompatible. Please review the section "Detection of Transaction Log Incompatibilities" in the c-treeACE Administrator’s Guide for details.