The exposure correction is currently not stored in the database. In addition to a database update, this would require a lot of new program code.

Maik

This information is stored in the EXIF information of the picture, and can be displayed e.g. in gwenview. I think this is a very useful information that can be very handy.
In  Panasonic DMC-FZ1000 it is stored in "Exposure Compensation".

Why is it hard coded anyway?

Extracting this information from file is very easy with digiKam core implementation. This is not the problem.

All elementary information shown in file properties view are stored also in the database. Why ? To perform quick search with this kind of element. This is the goal of photo DAM.

If we add a new property to show, we need also to store it in DB to be homogeneous. We cannot only show the value as well.

Gilles Caulier

It would be much more flexible and easier for the developer if the EXIF information was stored as key-value-pair and not as a dedicated row in the database

It's not about somehow saving the EXIF metadata in a BLOB field. It must also be possible to associate this data with SQL queries by e.g. to include all images with a focal length of > 100mm and an exposure compensation of -1.5 for a search request.

Maik

I did not mean to store all the EXIF data in a BLOB without structure, but to make a table "exif" or something like that, with key and value as columns and a foreign key to the picture file. This way it would be extensible (additional keys would be stored automatically) and you can query it for a key having a certain value or a range of values, even with an index.

That too would be possible, but it would be a major change. Alternatively, you can see the exposure correction from the selected image in the right metadata side bar. It is also possible to use a filter that only displays the metadata of interest to quickly find the exposure correction.

Maik

When it is not planned to keep the same database scheme like it was in the design phase and let it evolve, I think that a good time to do this is a change in the major version number (for example 5 to 6). I do not think that this is the only possible place that you thought "If only the database schema was different!", so that would be a good opportunity to do so.
Is the database schema version somehow persisted, so that the correct migration script can be selected?

How can be the name of the used EXIF fields be determined? I do not know what I did exactly, but all the displayed EXIF information vanished. I then decided to put the interesting fields back one after the other, and some fields are "nicht verfügbar" (probably in English it says "not available"). This applies e.g. to "Bildinformatione/Aperture Value", "Fotoinformationen/Aperture" and "Fotoinformationen/ISO Speed". "Fotoinformationen/Exposure Time" is available. After that, I gave up.
And how can I restore the originally shown values?

I added a few EXIF entries that are displayed, and suddenly 10 entries more than I selected are displayed. I have the tab on "EXIF", and when I click on the triangle left of the Search field, the "user defined" entries are selected.
When I click on "preferences", these entries are not selected. When I select them, and in the next round deselect them again, nothing happens. So this bug does not fill the marks wrongly, it displays wrongly.

Works here without problems. For example, there are the entries double for image information or photo information. Therefore, you have the "unavailable" display when you select the example of the focal length of image information, because this info is usually in photo information.

Maik

I have experimented a bit, and when I have a certain number of entries (5 or so, I do not know exactly), the effect appears. A few more, and the effect vanishes again.

Further observation: It seems to be necessary to have a field in the list that is not available.

Maik,

This is another Exif value to populate in database. Remember the time zone wish too reported in another bugzilla entry.

Gilles