ShowTableCreationCommand.java

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

import org.apache.doris.catalog.Column;
import org.apache.doris.catalog.ScalarType;
import org.apache.doris.common.ErrorCode;
import org.apache.doris.common.ErrorReport;
import org.apache.doris.common.util.ListComparator;
import org.apache.doris.common.util.OrderByPair;
import org.apache.doris.nereids.trees.plans.PlanType;
import org.apache.doris.nereids.trees.plans.visitor.PlanVisitor;
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 com.google.common.base.Strings;
import com.google.common.collect.Lists;

import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

/**
 * show table id command
 */
public class ShowTableCreationCommand extends ShowCommand {
    private static final ShowResultSetMetaData META_DATA =
            ShowResultSetMetaData.builder()
                .addColumn(new Column("Database", ScalarType.createVarchar(20)))
                .addColumn(new Column("Table", ScalarType.createVarchar(20)))
                .addColumn(new Column("Status", ScalarType.createVarchar(10)))
                .addColumn(new Column("Create Time", ScalarType.createVarchar(20)))
                .addColumn(new Column("Error Msg", ScalarType.createVarchar(100)))
                .build();

    private String dbName;
    private String wild;

    /**
     * constructor
     */
    public ShowTableCreationCommand(String dbName, String wild) {
        super(PlanType.SHOW_TABLE_CREATION_COMMAND);
        this.dbName = dbName;
        this.wild = wild;
    }

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

    @Override
    public ShowResultSet doRun(ConnectContext ctx, StmtExecutor executor) throws Exception {
        if (Strings.isNullOrEmpty(dbName)) {
            dbName = ConnectContext.get().getDatabase();
            if (Strings.isNullOrEmpty(dbName)) {
                ErrorReport.reportAnalysisException(ErrorCode.ERR_NO_DB_ERROR);
            }
        }

        /* Need to implement fetching records from iceberg table */
        List<List<Comparable>> rowSet = Lists.newArrayList();
        // sort function rows by fourth column (Create Time) asc
        ListComparator<List<Comparable>> comparator = null;
        OrderByPair orderByPair = new OrderByPair(3, false);
        comparator = new ListComparator<>(orderByPair);
        Collections.sort(rowSet, comparator);
        List<List<String>> resultRowSet = Lists.newArrayList();

        Set<String> keyNameSet = new HashSet<>();
        for (List<Comparable> row : rowSet) {
            List<String> resultRow = Lists.newArrayList();
            for (Comparable column : row) {
                resultRow.add(column.toString());
            }
            resultRowSet.add(resultRow);
            keyNameSet.add(resultRow.get(0));
        }

        return new ShowResultSet(getMetaData(), resultRowSet);
    }

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