What is the Difference between system initialization and update in hybris?

问题

I suppose it runs essentialdata.impex. I am not sure of the difference. Any inputs from hybris experts highly appreciated.

回答1:

• Initalization:

  1. Droping old and create new empty system.
  2. Creating schema and type system.
  3. Reloading persistences
  4. Clearing cache.
  5. Initialize media storages.
  6. Setting licence.
  7. Restarting internals.
  8. Clearing hMc configuration from database.
  9. creating essential data.
  10. Localizing types and creating project data.

• Updating

  1. Updating schema.
  2. Reloading persistences
  3. Clearing cache.
  4. Initialize media storages
  5. setting licence.

回答2:

Initialization drops existing type definitions from the database prior to rebuilding, so the entire type system is created from scratch. So during an initialization, type system definitions are created to match the type system definition in the items.xml files.

During an update, type system definitions are modified to match the new type system definition in the items.xml files.

During the initialization and update processes, the platform looks for ImpEx files in the /resources/impex folder. In particular:

• For essential data: The platform scans the /resources/impex folders for files with names that match the pattern essentialdata*.impex and imports the files during the essential data creation.
• For project data: The platform scans the /resources/impex folders for files with names that match the pattern projectdata*.impex and imports the files during the project data creation.

回答3:

In Update suppose you have done any change in attribute of items.xml then after update older will remain in table structure and newer will also create (it apply same for column also)

You need to intialize the system, only when you want to build the site from scratch or when you are creating new environemnt. like QA/Staging/Prod.

You will do system update - whenever you are making modifications to *items.xml file. like adding an itemtype or modifying existing item type or changing any restrictions etc..

来源：https://stackoverflow.com/questions/29936212/what-is-the-difference-between-system-initialization-and-update-in-hybris