LogicalSubQueryAliasToLogicalProject.java

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package org.apache.doris.nereids.rules.analysis;

import org.apache.doris.nereids.rules.Rule;
import org.apache.doris.nereids.rules.RuleType;
import org.apache.doris.nereids.rules.rewrite.OneRewriteRuleFactory;
import org.apache.doris.nereids.trees.plans.logical.LogicalProject;

import com.google.common.collect.ImmutableList;

/**
 * Eliminate the logical sub query and alias node after analyze and before rewrite
 * If we match the alias node and return its child node, in the execute() of the job
 * <p>
 * TODO: refactor group merge strategy to support the feature above
 */
public class LogicalSubQueryAliasToLogicalProject extends OneRewriteRuleFactory {
    @Override
    public Rule build() {
        return RuleType.LOGICAL_SUB_QUERY_ALIAS_TO_LOGICAL_PROJECT.build(
                logicalSubQueryAlias().thenApply(ctx -> {
                    LogicalProject project = new LogicalProject<>(
                            ImmutableList.copyOf(ctx.root.getOutput()), ctx.root.child());
                    return project;
                })
        );
    }
}