Error using pre-built materializations with JDBC schema sources

[Justin Swanhart]

I have several materialized views in a MySQL database that I would like to
use for materialized view rewrite.

For example I have a "materialized view" named mv_date_summary which for
simplicity could be created with:
create table mv_date_summary as select LO_OrderDateKey, D_Year, D_Month,
D_DayNumInMonth, count(*) the_cnt, sum(LO_Quantity * LO_ExtendedPrice)
the_sum from lineorder join dim_date on LO_OrderDateKey = D_DateKey group
by D_Year, D_Month, D_DayNumInMonth, LO_OrderDateKey;

I have created a model with the following JSON:
{
  version: '1.0',
  defaultSchema: 'ssb',
  schemas: [
    {
      name: 'ssb',
      type: 'jdbc',
        jdbcUrl: 'jdbc:mysql://localhost:3306/ssb',
        jdbcUser: 'root',
        jdbcPassword: '',

      materializations: [
        { table: "mv_date_summary",
 sql: "select \"LO_OrderDateKey\", \"D_Year\", \"D_Month\",
\"D_DayNumInMonth\", count(*) \"the_cnt\", sum(\"LO_Quantity\" *
\"LO_ExtendedPrice\") \"the_sum\" from \"ssb\".\"lineorder\" join
\"ssb\".\"dim_date\" on \"LO_OrderDateKey\" = \"D_DateKey\" group by
\"D_Year\", \"D_Month\", \"D_DayNumInMonth\", \"LO_OrderDateKey\""
}
      ]
    }
  ]
}

However, when I try to use the model in sqlline, I get an error:
Caused by: java.lang.RuntimeException: Cannot define materialization;
parent schema 'ssb' is not a SemiMutableSchema
at org.apache.calcite.model.ModelHandler.visit(ModelHandler.java:349)

I tried with CustomModel with a JDBC type factory, but I got the same error.