Downgrades the db specified in the connection config to a schema version.
mlmd.downgrade_schema(
config: mlmd.proto.ConnectionConfig
,
downgrade_to_schema_version: int
) -> None
If downgrade_to_schema_version
is greater or equals to zero and less than
the current library's schema version, it runs a downgrade transaction to
revert the db schema and migrate the data. The update is transactional, and
any failure will cause a full rollback of the downgrade. Once the downgrade
is done, the user needs to use the older version of the library to connect to
the database.
Args |
config
|
a proto.ConnectionConfig having the connection params.
|
downgrade_to_schema_version
|
downgrades the given database to a specific
version. For v0.13.2 release, the schema_version is 0. For 0.14.0 and
0.15.0 release, the schema_version is 4. More details are described in
g3doc/get_start#upgrade_mlmd_library
|
Raises |
errors.InvalidArgumentError
|
if the downgrade_to_schema_version is not
given or it is negative or greater than the library version.
|
RuntimeError
|
if the downgrade is not finished, return detailed error.
|