ShowCatalogCommand.java

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.doris.nereids.trees.plans.commands;

import org.apache.doris.catalog.Column;
import org.apache.doris.catalog.Env;
import org.apache.doris.catalog.ScalarType;
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 java.util.List;

/**
 * Represents the command for show all catalog or desc the specific catalog.
 */
public class ShowCatalogCommand extends ShowCommand {
    private static final ShowResultSetMetaData META_DATA_ALL =
            ShowResultSetMetaData.builder().addColumn(new Column("CatalogId", ScalarType.BIGINT))
                .addColumn(new Column("CatalogName", ScalarType.createVarchar(64)))
                .addColumn(new Column("Type", ScalarType.createStringType()))
                .addColumn(new Column("IsCurrent", ScalarType.createStringType()))
                .addColumn(new Column("CreateTime", ScalarType.createStringType()))
                .addColumn(new Column("LastUpdateTime", ScalarType.createStringType()))
                .addColumn(new Column("Comment", ScalarType.createStringType()))
                .build();

    private static final ShowResultSetMetaData META_DATA_SPECIFIC =
            ShowResultSetMetaData.builder()
                .addColumn(new Column("Key", ScalarType.createStringType()))
                .addColumn(new Column("Value", ScalarType.createStringType()))
                .build();

    private final String catalogName;
    private final String pattern;

    public ShowCatalogCommand(String catalogName, String pattern) {
        super(PlanType.SHOW_CATALOG_COMMAND);
        this.catalogName = catalogName;
        this.pattern = pattern;
    }

    @Override
    public ShowResultSet doRun(ConnectContext ctx, StmtExecutor executor) throws Exception {
        List<List<String>> rows = Env.getCurrentEnv().getCatalogMgr()
                .showCatalogs(catalogName, pattern, ctx.getCurrentCatalog() != null
                    ? ctx.getCurrentCatalog().getName() : null);

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

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

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append("SHOW");

        if (catalogName != null) {
            sb.append(" CATALOG ");
            sb.append(catalogName);
        } else {
            sb.append(" CATALOGS");

            if (pattern != null) {
                sb.append(" LIKE ");
                sb.append("'");
                sb.append(pattern);
                sb.append("'");
            }
        }

        return sb.toString();
    }

    public ShowResultSetMetaData getMetaData() {
        if (catalogName == null) {
            return META_DATA_ALL;
        } else {
            return META_DATA_SPECIFIC;
        }
    }
}