a cleaner way to handle this

[github-actions]

a cleaner way to handle this

wayang/wayang-api/wayang-api-sql/src/main/java/org/apache/wayang/api/sql/calcite/rules/WayangTableScanRule.java

Line 56 in c2bb03c

* TODO: a cleaner way to handle this

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to you under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
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 * http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.wayang.api.sql.calcite.rules;

import org.apache.calcite.adapter.enumerable.EnumerableConvention;
import org.apache.calcite.plan.Convention;
import org.apache.calcite.plan.RelOptTable;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.convert.ConverterRule;
import org.apache.calcite.rel.core.TableScan;
import org.apache.calcite.rel.logical.LogicalTableScan;

import org.apache.wayang.api.sql.calcite.convention.WayangConvention;
import org.apache.wayang.api.sql.calcite.rel.WayangTableScan;

public class WayangTableScanRule extends ConverterRule {
    public static final Config DEFAULT_CONFIG = Config.INSTANCE
            .withConversion(LogicalTableScan.class,
                    Convention.NONE, WayangConvention.INSTANCE,
                    "WayangTableScanRule")
            .withRuleFactory(WayangTableScanRule::new);

    public static final Config ENUMERABLE_CONFIG = Config.INSTANCE
            .withConversion(TableScan.class,
                    EnumerableConvention.INSTANCE, WayangConvention.INSTANCE,
                    "WayangTableScanRule1")
            .withRuleFactory(WayangTableScanRule::new);

    protected WayangTableScanRule(final Config config) {
        super(config);
    }

    @Override
    public RelNode convert(final RelNode relNode) {

        final TableScan scan = (TableScan) relNode;
        final RelOptTable relOptTable = scan.getTable();

        /**
         * This is quick hack to prevent volcano from merging projects on to TableScans
         * TODO: a cleaner way to handle this
         */
        if (relOptTable.getRowType() == scan.getRowType()) {
            return WayangTableScan.create(scan.getCluster(), relOptTable);
        }
        return null;
    }
}

788409a712294ed187f4a3a2f74a2523753e34f8

[C-byChloe]

I would like to work on this!

[AjayBoddeda4]

Hi, I am Ajay Boddeda, a GSoC 2026 applicant working on the DataFrames API proposal for Apache Wayang.
This issue is interesting from a DataFrame API perspective. The WayangTableScanRule is part of the SQL to Wayang plan conversion — which will be directly relevant when the DataFrame API needs to support SQL-style table scans through the Calcite optimizer.
A cleaner approach could be to check the projection fields explicitly rather than comparing row types directly. This would make the logic more readable and maintainable as the codebase grows with new features like the DataFrame API.
Happy to contribute to this if guidance is provided on the preferred approach.