We found a way to repair the overwritten column, table, and bucket user metadata, caused by the incident reported here: Column, table or bucket metadata possibly overwritten.
The incident affected column, table, and bucket metadata that had two (or more) metadata with the same key but a different provider. If metadata had been updated for one provider, values were changed for all of them. This could have led to a rewrite of user-defined metadata for column type, length, or any other metadata. These metadata are used for input mapping. Existing mappings were not affected. But you may be facing a problem when you create a new input mapping and use any table with affected metadata that works in existing mappings. This may cause a problem with the newly created input mapping. As a temporary solution, you can reset this user-defined metadata for a data type manually to the correct value.
We will find all affected metadata and obtain the correct values by “replaying” update metadata storage events. For all user metadata we fix, we also update the time stamp. While repairing the metadata, we will disable a project for a short time (we expect seconds or a few minutes at most), during which you will be unable to use the project. We apologize for any inconvenience. In the following days, we will add a message (shown on the project dashboard) to the affected projects with the expected date when the process to repair corrupted metadata will start.
Any changes to the metadata after the issue has been fixed (December 3, 9:03 UTC) will be also taken into account and will not be lost.