/*
* Copyright 2004-2023 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (https://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.table;
import org.h2.command.ddl.CreateSynonymData;
import org.h2.engine.SessionLocal;
import org.h2.message.DbException;
import org.h2.message.Trace;
import org.h2.schema.Schema;
import org.h2.schema.SchemaObject;
import org.h2.util.ParserUtil;
/**
* Synonym for an existing table or view. All DML requests are forwarded to the backing table.
* Adding indices to a synonym or altering the table is not supported.
*/
public class TableSynonym extends SchemaObject {
private CreateSynonymData data;
/**
* The table the synonym is created for.
*/
private Table synonymFor;
public TableSynonym(CreateSynonymData data) {
super(data.schema, data.id, data.synonymName, Trace.TABLE);
this.data = data;
}
/**
* @return the table this is a synonym for
*/
public Table getSynonymFor() {
return synonymFor;
}
/**
* Set (update) the data.
*
* @param data the new data
*/
public void updateData(CreateSynonymData data) {
this.data = data;
}
@Override
public int getType() {
return SYNONYM;
}
@Override
public String getCreateSQLForCopy(Table table, String quotedName) {
return synonymFor.getCreateSQLForCopy(table, quotedName);
}
@Override
public void rename(String newName) { throw DbException.getUnsupportedException("SYNONYM"); }
@Override
public void removeChildrenAndResources(SessionLocal session) {
synonymFor.removeSynonym(this);
database.removeMeta(session, getId());
}
@Override
public String getCreateSQL() {
StringBuilder builder = new StringBuilder("CREATE SYNONYM ");
getSQL(builder, DEFAULT_SQL_FLAGS).append(" FOR ");
ParserUtil.quoteIdentifier(builder, data.synonymForSchema.getName(), DEFAULT_SQL_FLAGS).append('.');
ParserUtil.quoteIdentifier(builder, data.synonymFor, DEFAULT_SQL_FLAGS);
return builder.toString();
}
@Override
public String getDropSQL() {
return getSQL(new StringBuilder("DROP SYNONYM "), DEFAULT_SQL_FLAGS).toString();
}
@Override
public void checkRename() {
throw DbException.getUnsupportedException("SYNONYM");
}
/**
* @return the table this synonym is for
*/
public String getSynonymForName() {
return data.synonymFor;
}
/**
* @return the schema this synonym is for
*/
public Schema getSynonymForSchema() {
return data.synonymForSchema;
}
/**
* @return true if this synonym currently points to a real table
*/
public boolean isInvalid() {
return synonymFor.isValid();
}
/**
* Update the table that this is a synonym for, to know about this synonym.
*/
public void updateSynonymFor() {
if (synonymFor != null) {
synonymFor.removeSynonym(this);
}
synonymFor = data.synonymForSchema.getTableOrView(data.session, data.synonymFor);
synonymFor.addSynonym(this);
}
}