Generating data unload and load commands for data preservation

Your changes might require that some tables be dropped, created, or dropped and recreated, such as when you drop a column from the middle of a table. You might need data unload commands to preserve data from the dropped table and data load commands to load the appropriate data into the newly created table when you make database changes, including undoing a change. You can generate data unload and load commands and map the tables from which to unload and then load the data from the Deployment Script Editor.
To generate data unload and load commands from the Deployment Script Editor, complete the following steps:
  1. On the Change Commands tab of the Deployment Script Editor, click Generate Change Commands. The Generate Change Commands wizard starts.
  2. Ensure that the Enable data preservation option on the first page of the wizard is checked, and complete the steps in the wizard for generating data unload and load commands.

    If data preservation is unchecked DB2® Change Management Expert will not attempt to generate data preservation commands even if they are needed. If data preservation is not needed DB2 Change Management Expert will not generate any data preservation commands.

    DB2 Change Management Expert generates default data preservation entries when it detects that data needs to be preserved. You can also add your own entries to associate data unload commands with their corresponding load commands. When the Customize field for an entry is set to Yes, the wizard includes pages that allow you to customize the data unload and load commands and map how data should be unloaded out of one table and loaded into another table. You can toggle the Customize field. DB2 Change Management Expert automatically sets the Customize field to Yes if it detects that you might need to customize the commands or map the columns.

    Important: Ensure that the data file names for your data unload and load commands are correct. Incorrect data file names can result in data loss. All data unload commands must specify unique data file names.

    Start of changeAlso, on the first page of the Deployment wizard, ensure that the Stop deployment if errors occur option is checked. If a command fails, you want to stop the deployment from continuing. If you do not stop the deployment on errors, data will be lost. End of change

  3. When you return to the Change Commands page, verify that data unload and load command files appear in the Define Change Commands field.

Your data unload and load commands are displayed in the appropriate order in the change commands list. Data unload commands are added first because you need to unload your data before you drop a column or table. Data load commands are added last.

You can view the syntax of your data unload and load commands in a text editor by selecting the file from within the Deployment Script Editor and clicking Edit.

Related concepts
Data preservation
Related tasks
Generating change commands from the Deployment Script Editor


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