Kexi/Plugins/Tables/Simple alter table
Design page for task: Simple approach to fulfill "Add support for alter table's design without losing data" wish.
- Started: Jstaniek (talk) August 2012
- Wish #125253
- Target: 2.6.0
Rationale
Approach when modification to table schema is saved directly after user performed it is much easier than full alter table tired in Kexi 1.x and never delivered.
Analysis
- Altering some physical properties would require immediate saving of the design but will not remove all the data.
- Other properties (for which KexiDB::isExtendedTableFieldProperty() return true) can be modified without altering any data.
Alter actions
This section publishes details on particular actions of table altering.
Caption rename
- triggers name change in property editor, so:
- A: if name changed, ask for accepting name change:
- if accepted go to Name change section
- if not accepted, revert the recent name change and go to B
- B: else, do nothing, caption should be saved on Save action
- A: if name changed, ask for accepting name change:
Name change
- can happen after change of caption (see Caption rename)
- can happen after changed name value in the property editor
- Algorithm:
Field removing
Field removing
Fields reordering
Field inserting
Requirements
- Full data safety
- It's better to warn and request data removal than claiming it is not necessary and then doing that