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+## Summary
+
+This document describes the portal database changes and its impact on transactional data. Depending on the impact, possible risks/impediments on upgrades as well as mitigation plans are described.
+Each section includes the respective change details, impact on existing data and the respective release with which the change is getting active.
+
+<br>
+
+> **_INFO:_** inside the detailed descriptions below, the definition 'migration script' refers to the term 'migrations' as it is defined by the ef-core framework: https://learn.microsoft.com/en-us/ef/core/managing-schemas/migrations
+
+
+<br>
+<br>
+
+#### Mediatype - NEW & ENHANCED - 1.2.0
+
+* NEW: table "media_types"
+* ENHANCED: table portal.documents "media_type_id" added
+
+Impact on existing data:
+As part of the migration, for all existing documents stored in the table portal.documents, the filename extension will be used to define and store the media_type_id of the respective document inside the new table attribute. Important: check beforehand if all documents have a document type added inside the document name. If not, add the respective media type or delete the document.
+Additionally check if all stored documents are supported by the media types migrated in table portal.media_type. In case any other document media type is currently loaded/stored inside the table portal.documents, the migration will fail. In this case delete the document beforehand or enhance the migration script media types supported.
+
+<br>
+
+Supported media types:
+
+media_type_id | media_type 
+--- | --- 
+1 | .jpg 
+1 | .jpeg
+2 | .gif
+3 | .png
+4 | .svg
+5 | .tif
+6 | .pdf
+7 | .json
+
+<br>
+
+> **_INFO:_** additional media types (e.g. .pem, .ca_cert, .pkx_cer, .octet)  are added in version 1.2.0 and 1.3.0
+
+
+<br>
+<br>
+
+#### Application Checklist - ENHANCED - 1.1.0
+
+* NEW: portal.processes
+* NEW: portal.process_types
+* ENHANCED: table company_applications "checklist_process_id" added
+* ENHANCED: table process_steps "process_id" added
+* REMOVED: removed table application_assigned_process_steps
+
+Impact on existing data:
+Existing company registration data currently under validation are automatically expanded with the respective attribute values for the new tables/attributes
+* processes
+* process_types
+* checklist_process_id
+* process_id
+
+No manual intervention needed.
+For company applications currently in status "under creation" (which means not yet submitted for validation) the change has no impact, since the process_id is created as part of the registration submitted. As soon as the participant submits the registration, the new process with the process_id will apply.
+
+<br>
+<br>
+
+#### Service Details - NEW (interim) - 1.1.0
+
+* NEW: table "service_details"
+* REMOVED: table service_assigned_service_types
+
+New service_detail table released to manage technical user need for services with a true/false flag.
+Attributes
+* service_id
+* service_type_id (connected to portal.service_types and replacing table service_assigned_service_types)
+* technical_user_needed (true/false flag)
+
+<img width="376" alt="image" src="https://user-images.githubusercontent.com/94133633/228341713-1bbc0354-0ebf-42f7-bc37-135567037b60.png">
+
+Impact on existing data:
+Migration script existing, based on the service type which is fetched for all existing data from portal table service_assigned_service_types, the technical_user_needed attribute is set to "true" for "DATASPACE_SERVICE" services and "false" for "CONSULTANCE_SERVICE".
+Transactional data are automatically updated/migrated. 
+
+<br>
+
+> **_INFO:_** Please note: this is an interim solution which is expected to get replaced/changed in version 1.4.0
+
+<br>
+<br>