When a module is upgraded, the data file loading is repeated, and the module's records are rewritten. It is important to keep in mind that this means that upgrading a module will overwrite any manual changes that might have been made to the module's data.
Notably, if views were manually modified to add customization, these changes will be lost with the next module upgrade. To avoid this, the correct approach is to instead create inherited views with the changes we want to introduce.
This rewrite behavior is the default, but it can be changed so that some of the data is only imported at install time, and is ignored in later module upgrades. This is done using the noupdate="1" attribute in the <odoo> or <data> elements. ...
