/********************************************************************************** * $URL: https://source.sakaiproject.org/svn/kernel/trunk/kernel-util/src/main/java/org/sakaiproject/util/DoubleStorageSqlMySql.java $ * $Id: DoubleStorageSqlMySql.java 101656 2011-12-12 22:40:28Z aaronz@vt.edu $ *********************************************************************************** * * Copyright (c) 2007, 2008 Sakai Foundation * * Licensed under the Educational Community License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.opensource.org/licenses/ECL-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * **********************************************************************************/ package org.sakaiproject.util; /** * methods for accessing double storage data in a mysql database. */ public class DoubleStorageSqlMySql extends DoubleStorageSqlDefault { /** * Return a record ID to use internally in the database. This is needed for databases (MySQL) that have limits on key lengths. The hash code * ensures that the record ID will be unique, even if the DB only considers a prefix of a very long record ID. * * @param recordId * @return The record ID to use internally in the database */ public String getRecordId(String recordId) { if (recordId == null) recordId = "null"; return recordId.hashCode() + " - " + recordId; } // MySql supports the limit operation at the end of the Query so this is pretty easy @Override public String addLimitToQuery(String sqlIn, int startRec, int endRec) { int recordCount = (endRec-startRec)+1; return sqlIn + " limit "+startRec+","+recordCount; } }