The following procedure describes the general tasks you must perform for file format conversions:
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Modify the database description.
Insert the UPDATE statement in front of the database description. This statement instructs the DASDL compiler to update an existing database description, creating a new description file.
New attributes can be specified for the structures being reorganized. The tables in Update, Reorganization, and Modeling Capabilities and Limitations indicate which changes are allowed during a file format conversion.
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Compile the database description.
The new database description file produced during the compilation contains information about both the new and old file formats.
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Run the BUILDREORG program using the database description file produced in step 2. This action creates a reorganization description file.
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Generate the Reorganization program using the reorganization description file produced in step 3.
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Compile the DMSUPPORT library using the new database description file produced in step 2. The title of the new DMSUPPORT library must include the new update level of the database. For example, if the new database update level is 2, and the database is not a permanent directory database, the title is DMSUPPORT/<database name>/2. If it is a permanent directory database, the default title is <path name>/DMSUPPORT/<database name>/2. If you set the compiler control option to ZIP, this step occurs automatically.
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Before continuing the reorganization on a system that has the DMALGOLUNSAFE option set, use the MP system command with the EXECUTABLE option to make the newly compiled DMSUPPORT library in an executable code file. For more information on the DMALGOLUNSAFE option, see the Security Overview and Implementation Guide. For more information on the MP system command, see the System Commands Operations Reference Manual.
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Run the Reorganization program. Make sure that both the new and the old DMSUPPORT library and the new database description file produced in step 2 are present.
The Reorganization program reads the old data set, set, or subset and generates a new one in the new format. When the reorganization process is complete, the new structure replaces the old structure, and the old structure is removed.
User programs can access the database while the reorganization is in progress.
Since record formats are not changed, existing user programs do not need to be recompiled.
