Adding two collection items, only saves one, causes SQL error when deleting

[milosa]

Contenttype:

        site_images:
            label: Site foto's
            type: collection
            fields:
                header_image:
                    label: Site foto
                    type: set
                    fields:
                        image:
                            type: image
                            alt: true
                            upload: images

Details

Question	Answer
Relevant Bolt Version	4 RC25
Install type	Composer install
PHP version	7.4.7
Web server	symfony
Database	sqllite

Reproduction

Start with empty content type.

Then add one image to the collection. But don't save the contenttype content.
Add another item (with image) to the collection.

Now click save.

Problem 1: Only the first image is displayed in the collection. The second collection item is displayed, but it is empty. (No image)

Problem 2: Hit remove item on the empty collection item, then clicking save, causes this SQL error:

php.CRITICAL: Error: Uncaught PDOException: SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: bolt_field.content_id in (...)/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php:127 Stack trace: 
#0 (...)/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php(127): PDOStatement->execute(NULL) 
#1 (...)/vendor/doctrine/dbal/lib/Doctrine/DBAL/Statement.php(153): Doctrine\DBAL\Driver\PDOStatement->execute(NULL) 
#2 (...)/vendor/doctrine/orm/lib/Doctrine/ORM/Persisters/Entity/BasicEntityPersister.php(286): Doctrine\DBAL\Statement->execute() 
#3 (...)/vendor/doctrine/orm/lib/Doctrine/ORM/UnitOfWork.php(1087): Doctrine\ORM\Persisters\Entity\BasicEntityPersister->executeInserts() 
#4 (...)/vendor/doctrine/orm/lib/Doctrine/ORM/UnitOfWork.php( {"exception":"[object] (Symfony\\Component\\Debug\\Exception\\FatalThrowableError(code: 0): Error: Uncaught PDOException: SQLSTATE[23000]: Integrity constraint violation: 19 NOT NULL constraint failed: bolt_field.content_id in (...)/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php:127\nStack trace:\n
#0 (...)/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php(127): PDOStatement->execute(NULL)\n
#1 (...)/vendor/doctrine/dbal/lib/Doctrine/DBAL/Statement.php(153): Doctrine\\DBAL\\Driver\\PDOStatement->execute(NULL)\n
#2 (...)/vendor/doctrine/orm/lib/Doctrine/ORM/Persisters/Entity/BasicEntityPersister.php(286): Doctrine\\DBAL\\Statement->execute()\n
#3 (...)/vendor/doctrine/orm/lib/Doctrine/ORM/UnitOfWork.php(1087): Doctrine\\ORM\\Persisters\\Entity\\BasicEntityPersister->executeInserts()\n
#4 (...)/vendor/doctrine/orm/lib/Doctrine/ORM/UnitOfWork.php( at (...)/vendor/symfony/http-kernel/Controller/ControllerResolver.php:88)"} []

[milosa]

I'm getting some other weird behavior as well.
I forgot to enter the alt field of the second image. So I did this. Saved the content type.

Then I got a similar error

[2020-06-19 10:32:07] request.CRITICAL: Uncaught PHP Exception Doctrine\DBAL\Exception\NotNullConstraintViolationException: "An exception occurred while executing 'INSERT INTO bolt_field (name, sortorder, version, content_id, parent_id, type) VALUES (?, ?, ?, ?, ?, ?)'

But now both my collection items are empty (not showing an image in the backend).

Edit: It's now to the point that I can't use the collection anymore. Editing an item (the alt attribute) causes it to remove the images from all other items in the collection. (or at least it stops showing them)

When I add a new item, it stops showing the images in the existing items.

[I-Valchev]

Nice spot, interesting that it only happens in such specific cases. A fix is in the pipeline :-)