ShowColumnsCommand.java
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// to you under the Apache License, Version 2.0 (the
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//
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package org.apache.doris.nereids.trees.plans.commands;
import org.apache.doris.catalog.Column;
import org.apache.doris.catalog.DatabaseIf;
import org.apache.doris.catalog.Env;
import org.apache.doris.catalog.ScalarType;
import org.apache.doris.catalog.TableIf;
import org.apache.doris.common.AnalysisException;
import org.apache.doris.common.CaseSensibility;
import org.apache.doris.common.ErrorCode;
import org.apache.doris.common.ErrorReport;
import org.apache.doris.common.PatternMatcher;
import org.apache.doris.common.PatternMatcherWrapper;
import org.apache.doris.mysql.privilege.PrivPredicate;
import org.apache.doris.nereids.analyzer.UnboundSlot;
import org.apache.doris.nereids.trees.expressions.Expression;
import org.apache.doris.nereids.trees.expressions.visitor.DefaultExpressionRewriter;
import org.apache.doris.nereids.trees.plans.PlanType;
import org.apache.doris.nereids.trees.plans.commands.info.AliasInfo;
import org.apache.doris.nereids.trees.plans.commands.info.TableNameInfo;
import org.apache.doris.nereids.trees.plans.logical.LogicalPlan;
import org.apache.doris.nereids.trees.plans.visitor.PlanVisitor;
import org.apache.doris.nereids.util.Utils;
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.ArrayList;
import java.util.List;
import java.util.Locale;
/**
* Represents the SHOW COLUMNS command.
*/
public class ShowColumnsCommand extends ShowCommand {
private static final ShowResultSetMetaData META_DATA = ShowResultSetMetaData.builder()
.addColumn(new Column("Field", ScalarType.createVarchar(20)))
.addColumn(new Column("Type", ScalarType.createVarchar(20)))
.addColumn(new Column("Null", ScalarType.createVarchar(20)))
.addColumn(new Column("Key", ScalarType.createVarchar(20)))
.addColumn(new Column("Default", ScalarType.createVarchar(20)))
.addColumn(new Column("Extra", ScalarType.createVarchar(20))).build();
private static final ShowResultSetMetaData META_DATA_VERBOSE =
ShowResultSetMetaData.builder()
.addColumn(new Column("Field", ScalarType.createVarchar(20)))
.addColumn(new Column("Type", ScalarType.createVarchar(20)))
.addColumn(new Column("Collation", ScalarType.createVarchar(20)))
.addColumn(new Column("Null", ScalarType.createVarchar(20)))
.addColumn(new Column("Key", ScalarType.createVarchar(20)))
.addColumn(new Column("Default", ScalarType.createVarchar(20)))
.addColumn(new Column("Extra", ScalarType.createVarchar(20)))
.addColumn(new Column("Privileges", ScalarType.createVarchar(20)))
.addColumn(new Column("Comment", ScalarType.createVarchar(20)))
.build();
private final boolean isFull;
private TableNameInfo tableNameInfo;
private final String databaseName;
private final String likePattern;
private final Expression whereClause;
/**
* SHOW COLUMNS command Constructor.
*/
public ShowColumnsCommand(boolean isFull, TableNameInfo tableNameInfo, String databaseName, String likePattern,
Expression whereClause) {
super(PlanType.SHOW_COLUMNS_COMMAND);
this.isFull = isFull;
this.tableNameInfo = tableNameInfo;
this.databaseName = databaseName;
this.likePattern = likePattern;
this.whereClause = whereClause;
}
/**
* SHOW COLUMNS validate.
*/
public void validate(ConnectContext ctx) throws AnalysisException {
if (!Strings.isNullOrEmpty(databaseName)) {
tableNameInfo.setDb(databaseName);
}
tableNameInfo.analyze(ctx);
if (!Env.getCurrentEnv().getAccessManager()
.checkTblPriv(ConnectContext.get(), tableNameInfo.getCtl(), tableNameInfo.getDb(),
tableNameInfo.getTbl(), PrivPredicate.SHOW)) {
ErrorReport.reportAnalysisException(ErrorCode.ERR_TABLE_ACCESS_DENIED_ERROR,
PrivPredicate.SHOW.getPrivs().toString(), tableNameInfo);
}
}
/**
* replaceColumnNameVisitor
* replace column name to real column name
*/
private static class ReplaceColumnNameVisitor extends DefaultExpressionRewriter<Void> {
@Override
public Expression visitUnboundSlot(UnboundSlot slot, Void context) {
String name = slot.getName().toLowerCase(Locale.ROOT);
switch (name) {
case "field":
return UnboundSlot.quoted("COLUMN_NAME");
case "type":
return UnboundSlot.quoted("COLUMN_TYPE");
case "null":
return UnboundSlot.quoted("IS_NULLABLE");
case "default":
return UnboundSlot.quoted("COLUMN_DEFAULT");
case "comment":
return UnboundSlot.quoted("COLUMN_COMMENT");
default:
return slot;
}
}
}
@Override
public ShowResultSet doRun(ConnectContext ctx, StmtExecutor executor) throws Exception {
validate(ctx);
if (whereClause != null) {
Expression rewritten = whereClause.accept(new ReplaceColumnNameVisitor(), null);
String whereCondition = " WHERE TABLE_NAME = '" + tableNameInfo.getTbl() + "' AND " + rewritten.toSql();
TableNameInfo info = new TableNameInfo(tableNameInfo.getCtl(), "information_schema", "columns");
List<AliasInfo> selectList = new ArrayList<>();
if (isFull) {
selectList.add(AliasInfo.of("COLUMN_NAME", "Field"));
selectList.add(AliasInfo.of("COLUMN_TYPE", "Type"));
selectList.add(AliasInfo.of("COLLATION_NAME", "Collation"));
selectList.add(AliasInfo.of("IS_NULLABLE", "Null"));
selectList.add(AliasInfo.of("COLUMN_KEY", "Key"));
selectList.add(AliasInfo.of("COLUMN_DEFAULT", "Default"));
selectList.add(AliasInfo.of("EXTRA", "Extra"));
selectList.add(AliasInfo.of("PRIVILEGES", "Privileges")); // optional, can be set to ''
selectList.add(AliasInfo.of("COLUMN_COMMENT", "Comment"));
} else {
selectList.add(AliasInfo.of("COLUMN_NAME", "Field"));
selectList.add(AliasInfo.of("COLUMN_TYPE", "Type"));
selectList.add(AliasInfo.of("IS_NULLABLE", "Null"));
selectList.add(AliasInfo.of("COLUMN_KEY", "Key"));
selectList.add(AliasInfo.of("COLUMN_DEFAULT", "Default"));
selectList.add(AliasInfo.of("EXTRA", "Extra"));
}
LogicalPlan plan = Utils.buildLogicalPlan(selectList, info, whereCondition);
List<List<String>> rows = Utils.executePlan(ctx, executor, plan);
for (List<String> row : rows) {
String rawType = row.get(1);
row.set(1, normalizeSqlColumnType(rawType));
}
return new ShowResultSet(getMetaData(), rows);
}
List<List<String>> rows = Lists.newArrayList();
String ctl = tableNameInfo.getCtl();
DatabaseIf db = Env.getCurrentEnv().getCatalogMgr().getCatalogOrAnalysisException(ctl)
.getDbOrAnalysisException(tableNameInfo.getDb());
TableIf table = db.getTableOrAnalysisException(tableNameInfo.getTbl());
PatternMatcher matcher = null;
if (likePattern != null) {
matcher = PatternMatcherWrapper.createMysqlPattern(likePattern,
CaseSensibility.COLUMN.getCaseSensibility());
}
table.readLock();
try {
List<Column> columns = table.getBaseSchema();
for (Column col : columns) {
if (matcher != null && !matcher.match(col.getName())) {
continue;
}
final String columnName = col.getName();
final String columnType = col.getOriginType().toString().toLowerCase(Locale.ROOT);
final String isAllowNull = col.isAllowNull() ? "YES" : "NO";
final String isKey = col.isKey() ? "YES" : "NO";
final String defaultValue = col.getDefaultValue();
final String aggType = col.getAggregationType() == null ? "" : col.getAggregationType().toSql();
if (isFull) {
// Field Type Collation Null Key Default Extra
// Privileges Comment
rows.add(Lists.newArrayList(columnName,
columnType,
"",
isAllowNull,
isKey,
defaultValue,
aggType,
"",
col.getComment()));
} else {
// Field Type Null Key Default Extra
rows.add(Lists.newArrayList(columnName,
columnType,
isAllowNull,
isKey,
defaultValue,
aggType));
}
}
} finally {
table.readUnlock();
}
return new ShowResultSet(getMetaData(), rows);
}
@Override
public <R, C> R accept(PlanVisitor<R, C> visitor, C context) {
return visitor.visitShowColumnsCommand(this, context);
}
@Override
public ShowResultSetMetaData getMetaData() {
if (isFull) {
return META_DATA_VERBOSE;
} else {
return META_DATA;
}
}
private static String normalizeSqlColumnType(String type) {
if (type == null) {
return null;
}
type = type.toLowerCase().trim();
if (type.matches("^[a-z]+\\s*\\(.*\\)$")) {
int parenIndex = type.indexOf('(');
return type.substring(0, parenIndex).trim();
}
return type;
}
}