I ran into a bug today that was caused by this. It's surprising that you cannot set an embedded object to null and have all columns be null. It seems to just be ignored.

Seen this also. Really against my preference to collapse embedded entities to the top-level entity, but that's what I've had to do for now.

As well as this, if all embedded columns are null on load, it's not possible to use the field in the top-level entity as a check.

e.g. if I had an embedded Address entity, the absence of address data can't be checked simply with entity.address. Each field in the embedded entity needs to be checked: entity.address.lineOne, entity.address.lineTwo, etc.

This isn't exactly the same problem as this issue, but I feel it's in the same realm, where it would be nice to be able to read/write null from/to the columns in the embedded entity through the top-level entity.

As well as this, if all embedded columns are null on load, it's not possible to use the field in the top-level entity as a check.

e.g. if I had an embedded Address entity, the absence of address data can't be checked simply with entity.address. Each field in the embedded entity needs to be checked: entity.address.lineOne, entity.address.lineTwo, etc.

This isn't exactly the same problem as this issue, but I feel it's in the same realm, where it would be nice to be able to read/write null from/to the columns in the embedded entity through the top-level entity.

That is true and leads to a subtle bug in my case. Unfortunately, there is no transformer option on ColumnEmbeddedOptions, so I came up with this solution.

Firstly we need a function that returns null when all object properties are null.

export function asNullOnNullProperties<T>(obj: T): T | null {
  for (const key in obj) {
    if (obj[key] != null) {
      return obj;
    }
  }
  return null;
}

Now we can use some listeners to modify the embedded entity value. It depends on your use case, but this should be enough.

@AfterLoad()
@AfterInsert()
@AfterUpdate()
handleEmbeddedEntities() {
  this.myEmbeddedEntity = asNullOnNullProperties(this.myEmbeddedEntity);
}

Hope it helps 👍