ShowConstraintsCommand.java

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package org.apache.doris.nereids.trees.plans.commands;

import org.apache.doris.analysis.StmtType;
import org.apache.doris.catalog.Column;
import org.apache.doris.catalog.ScalarType;
import org.apache.doris.catalog.TableIf;
import org.apache.doris.nereids.trees.plans.PlanType;
import org.apache.doris.nereids.trees.plans.visitor.PlanVisitor;
import org.apache.doris.nereids.util.RelationUtil;
import org.apache.doris.qe.ConnectContext;
import org.apache.doris.qe.ShowResultSet;
import org.apache.doris.qe.ShowResultSetMetaData;
import org.apache.doris.qe.StmtExecutor;

import org.apache.hadoop.util.Lists;

import java.util.List;
import java.util.Optional;
import java.util.stream.Collectors;

/**
 * add constraint command
 */
public class ShowConstraintsCommand extends ShowCommand {

    private static final ShowResultSetMetaData META_DATA = ShowResultSetMetaData.builder()
            .addColumn(new Column("Name", ScalarType.createVarchar(20)))
            .addColumn(new Column("Type", ScalarType.createVarchar(20)))
            .addColumn(new Column("Definition", ScalarType.createVarchar(20)))
            .build();

    private final List<String> nameParts;

    /**
     * constructor
     */
    public ShowConstraintsCommand(List<String> nameParts) {
        super(PlanType.SHOW_CONSTRAINTS_COMMAND);
        this.nameParts = nameParts;
    }

    @Override
    public ShowResultSetMetaData getMetaData() {
        return META_DATA;
    }

    @Override
    public ShowResultSet doRun(ConnectContext ctx, StmtExecutor executor) throws Exception {
        TableIf tableIf = RelationUtil.getDbAndTable(
                RelationUtil.getQualifierName(ctx, nameParts), ctx.getEnv(), Optional.empty()).value();
        tableIf.readLock();
        List<List<String>> res;
        try {
            res = tableIf.getConstraintsMap().entrySet().stream()
                    .map(e -> Lists.newArrayList(e.getKey(),
                            e.getValue().getType().getName(),
                            e.getValue().toString()))
                    .collect(Collectors.toList());
        } finally {
            tableIf.readUnlock();
        }
        return new ShowResultSet(META_DATA, res);
    }

    @Override
    public <R, C> R accept(PlanVisitor<R, C> visitor, C context) {
        return visitor.visitShowConstraintsCommand(this, context);
    }

    @Override
    public StmtType stmtType() {
        return StmtType.SHOW;
    }
}