/**
* com.mckoi.database.interpret.Set 14 Sep 2001
*
* Mckoi SQL Database ( http://www.mckoi.com/database )
* Copyright (C) 2000, 2001, 2002 Diehl and Associates, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* Version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License Version 2 for more details.
*
* You should have received a copy of the GNU General Public License
* Version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Change Log:
*
*
*/
package com.mckoi.database.interpret;
import java.util.ArrayList;
import java.util.List;
import java.math.BigDecimal;
import com.mckoi.database.*;
/**
* The SQL SET statement. Sets properties within the current local database
* connection such as auto-commit mode.
*
* @author Tobias Downer
*/
public class Set extends Statement {
/**
* The type of set this is.
*/
String type;
/**
* The variable name of this set statement.
*/
String var_name;
/**
* The Expression that is the value to assign the variable to
* (if applicable).
*/
Expression exp;
/**
* The value to assign the value to (if applicable).
*/
String value;
// ---------- Implemented from Statement ----------
public void prepare() throws DatabaseException {
type = (String) cmd.getObject("type");
var_name = (String) cmd.getObject("var_name");
exp = (Expression) cmd.getObject("exp");
value = (String) cmd.getObject("value");
}
public Table evaluate() throws DatabaseException {
DatabaseQueryContext context = new DatabaseQueryContext(database);
String com = type.toLowerCase();
if (com.equals("varset")) {
database.setVar(var_name, exp);
}
else if (com.equals("isolationset")) {
value = value.toLowerCase();
database.setTransactionIsolation(value);
}
else if (com.equals("autocommit")) {
value = value.toLowerCase();
if (value.equals("on") ||
value.equals("1")) {
database.setAutoCommit(true);
}
else if (value.equals("off") ||
value.equals("0")) {
database.setAutoCommit(false);
}
else {
throw new DatabaseException("Unrecognised value for SET AUTO COMMIT");
}
}
else if (com.equals("schema")) {
// It's particularly important that this is done during exclusive
// lock because SELECT requires the schema name doesn't change in
// mid-process.
// Change the connection to the schema
database.setDefaultSchema(value);
}
else {
throw new DatabaseException("Unrecognised set command.");
}
return FunctionTable.resultTable(context, 0);
}
}
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