Release 10.1A: OpenEdge Development:
Progress Dynamics Administration

DCU processing sequence

When you design deployment programs, you must consider the sequence in which the DCU applies your programs. Deploying a single version of your application might require several passes through the DCU’s processing stages. A patch level is all the programs that run during one pass.

The DCU processing sequence runs as follows:

The DCU parses all the XML files, loading the data into a temp table, and writing it to the Repository.
It sorts the temp table records by patch level and stage.
It processes Stages 1–6 for the first patch level.
It repeats the process for the remaining patch levels in ascending order.
The DCU stops when it reaches one of the following end conditions:
A mandatory patch returns an error.
The DCU completes Stage 6 processing for the final patch level.
The DCU writes the status of the upgrade process and a list of patches that still must be completed to the Repository.
When the next user who can change system data starts a Progress Dynamics session that has a direct database connection, the framework checks for information on unfinished upgrades in the Repository.
If there are unfinished upgrades to apply, the framework starts the DCU.
Beginning with the first unapplied patch level, the DCU works its way through Stages 7–9 for each patch level in ascending order.