some question when using calcite to rewrite materialized views query

[王仁杰 <wa...@std.uestc.edu.cn>]

hello,I am a novice user of calcite and want to implement a graduation project throught calcit.but i face some question when i want to rewrite materialized views query.

this is my create table and create materialize view Sql,I create a table with attr1 and attr2 columns,and create a materialized view with filter attr1>10 on this table:

        String sql = "create table opttable (attr1 int, attr2 int)";
        String mvsql = "create materialized view if not exists optmv " +
                "as select attr1,attr2 from opttable where attr1 >10";


I want to use HBO to rewrite my materialized view query,and below is my rule and query sql:

        HepProgramBuilder builder = new HepProgramBuilder();
        builder.addRuleInstance(MaterializedViewRules.FILTER);
        HepPlanner hepPlanner = new HepPlanner(builder.build());




next ,I add materialized view to HBO planner:

       String querySql = mView.getView().getQuery();
       Planner planner = Frameworks.getPlanner(config);
      SqlNode sqlNode = planner.parse(querySql);
      planner.validate(sqlNode);
      RelRoot relRoot = planner.rel(sqlNode);
      RelNode relNode = relRoot.project();
      if (null == cluster) {
        cluster = relRoot.rel.getCluster();
      }
      final RelDataTypeFactory typeFactory = cluster.getTypeFactory();


      CalciteCatalogReader catalogReader =
          new CalciteCatalogReader(
              prepareContext.getRootSchema(),
              prepareContext.getDefaultSchemaPath(),
              typeFactory,
              prepareContext.config());


      RelNode queryRel=relNode;
      RelBuilder relBuilder = RelFactories.LOGICAL_BUILDER.create(cluster, catalogReader);
      final RelNode replacement = relBuilder.scan("optmv").build();
      RelOptMaterialization materialization =
          new RelOptMaterialization(tableScan, queryRel, null, ImmutableList.of("default", "optmv"));
      relOptPlanner.addMaterialization(materialization);




but,when i execute sql:select attr1 from opttable where attr1 >9, this program face crash.I debug this and find that FILTER operator and UNION operator be child of each other,and program trap in loop.

I wonder if you can give me some advice. Thank you very much!