ListQuery.java

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package org.apache.doris.nereids.trees.expressions;

import org.apache.doris.nereids.trees.expressions.visitor.ExpressionVisitor;
import org.apache.doris.nereids.trees.plans.logical.LogicalPlan;
import org.apache.doris.nereids.types.DataType;

import com.google.common.base.Preconditions;

import java.util.List;
import java.util.Objects;
import java.util.Optional;

/**
 * Encapsulate LogicalPlan as Expression.
 * just for subquery.
 */
public class ListQuery extends SubqueryExpr {

    public ListQuery(LogicalPlan subquery) {
        super(Objects.requireNonNull(subquery, "subquery can not be null"));
    }

    public ListQuery(LogicalPlan subquery, List<Slot> correlateSlots, Optional<Expression> typeCoercionExpr) {
        super(subquery, correlateSlots, typeCoercionExpr);
    }

    @Override
    public DataType getDataType() {
        Preconditions.checkArgument(queryPlan.getOutput().size() == 1);
        return typeCoercionExpr.orElse(queryPlan.getOutput().get(0)).getDataType();
    }

    @Override
    public String computeToSql() {
        return " (LISTQUERY) " + super.computeToSql();
    }

    @Override
    public String toString() {
        return " (LISTQUERY) " + super.toString();
    }

    public <R, C> R accept(ExpressionVisitor<R, C> visitor, C context) {
        return visitor.visitListQuery(this, context);
    }

    @Override
    public Expression withTypeCoercion(DataType dataType) {
        return new ListQuery(queryPlan, correlateSlots,
                dataType == queryPlan.getOutput().get(0).getDataType()
                    ? Optional.of(queryPlan.getOutput().get(0))
                    : Optional.of(new Cast(queryPlan.getOutput().get(0), dataType)));
    }

    @Override
    public ListQuery withSubquery(LogicalPlan subquery) {
        return new ListQuery(subquery, correlateSlots, typeCoercionExpr);
    }
}