Primary Key column has always NOT NULL after using update command

[marcindyjas]

Descripton:

Primary Key column is always not nullable after using update command but according to documentation on Cloud Spanner:
https://cloud.google.com/spanner/docs/schema-and-data-model#notes_about_key_columns
Primary Key columns can be defined to store NULLs.

Steps to reproduce:

Use changeLog as below:

databaseChangeLog:
- changeSet:
    id: 1617793276323-1
    author: author
    changes:
    - createTable:
        columns:
        - column:
            constraints:
              primaryKey: true
              primaryKeyName: PRIMARY_KEY
            name: FIRST_1
            type: STRING(1024)
        - column:
            constraints:
              nullable: false
              primaryKey: true
              primaryKeyName: PRIMARY_KEY
            name: FIRST_2
            type: STRING(MAX)
        - column:
            constraints:
              primaryKey: true
              primaryKeyName: PRIMARY_KEY
            name: FIRST_3
            type: INT64
        - column:
            name: FIRST_4
            type: INT64
        tableName: FIRST_TABLE

In command:
liquibase --url="jdbc:cloudspanner:/projects/<project_name>/instances/<instance_name>/databases/<db_name>" --changeLogFile=changeLog.yml update

After that in schema you can see all Primary Keys as a not nullable but should be only FIRST_2 column.
Even adding "nullable: true" does not help.

[olavloite]

Hmm... The default behavior in Liquibase seems to be to assume that any primary key column should also be NOT NULL:

https://github.com/liquibase/liquibase/blob/99308bdebc8cd45142c3e2b8824838d9bd22ea21/liquibase-core/src/main/java/liquibase/statement/core/CreateTableStatement.java#L121