AutoML tables: changing just a col's data type apparently also changes the nullability status

[amygdala]

With the automl tables client libs, I'm seeing that a call like this to change the data type of a column, where that column is initially set to be Nullable:

client.update_column_spec(
          dataset_display_name='my dataset',
          column_spec_display_name='col_name',
          type_code='CATEGORY')

also changes the nullability-- it changes the col to from nullable to non-nullable.

(I haven't tried the case where the col starts out as non-nullable).

(The wrapper code looks okay on the face of it... )

[amygdala]

Explicitly setting nullable=True in the call does the right thing, so I'm guessing it's a False vs None logic error somewhere.

[helinwang]

Thanks for finding the issue Amy! Seems the problem is the code did not use update_mask. So the nullable field is overridden with the proto default value (False). I will send a fix for it.

[munkhuushmgl]

@helinwang Hey is there any update or internal bug logged somewhere?

[amygdala]

b/148677380

[kweinmeister]

Closing this issue for now, but please reopen if you are seeing this behavior.