org.h2.command.ddl.CreateConstant Maven / Gradle / Ivy
/*
* Copyright 2004-2019 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.command.ddl;
import org.h2.api.ErrorCode;
import org.h2.command.CommandInterface;
import org.h2.engine.Database;
import org.h2.engine.Session;
import org.h2.expression.Expression;
import org.h2.message.DbException;
import org.h2.schema.Constant;
import org.h2.schema.Schema;
import org.h2.value.Value;
/**
* This class represents the statement
* CREATE CONSTANT
*/
public class CreateConstant extends SchemaCommand {
private String constantName;
private Expression expression;
private boolean ifNotExists;
public CreateConstant(Session session, Schema schema) {
super(session, schema);
}
public void setIfNotExists(boolean ifNotExists) {
this.ifNotExists = ifNotExists;
}
@Override
public int update() {
session.commit(true);
session.getUser().checkAdmin();
Database db = session.getDatabase();
if (getSchema().findConstant(constantName) != null) {
if (ifNotExists) {
return 0;
}
throw DbException.get(ErrorCode.CONSTANT_ALREADY_EXISTS_1, constantName);
}
int id = getObjectId();
Constant constant = new Constant(getSchema(), id, constantName);
expression = expression.optimize(session);
Value value = expression.getValue(session);
constant.setValue(value);
db.addSchemaObject(session, constant);
return 0;
}
public void setConstantName(String constantName) {
this.constantName = constantName;
}
public void setExpression(Expression expr) {
this.expression = expr;
}
@Override
public int getType() {
return CommandInterface.CREATE_CONSTANT;
}
}