| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache 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.apache.org/licenses/LICENSE-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.apache.empire.dbms.oracle; |
| |
| import java.util.List; |
| |
| import org.apache.empire.commons.StringUtils; |
| import org.apache.empire.db.DBCommand; |
| import org.apache.empire.db.DBIndex; |
| import org.apache.empire.db.DBRowSet; |
| import org.apache.empire.db.expr.compare.DBCompareExpr; |
| import org.apache.empire.db.expr.join.DBColumnJoinExpr; |
| import org.apache.empire.db.expr.join.DBJoinExpr; |
| import org.apache.empire.db.expr.set.DBSetExpr; |
| import org.apache.empire.exceptions.InvalidArgumentException; |
| import org.apache.empire.exceptions.ObjectNotValidException; |
| |
| /** |
| * This class handles the special features of an oracle database. |
| * |
| * |
| */ |
| public class DBCommandOracle extends DBCommand |
| { |
| // *Deprecated* private static final long serialVersionUID = 1L; |
| |
| // Oracle Connect By / Start With |
| protected DBCompareExpr connectBy = null; |
| protected DBCompareExpr startWith = null; |
| // optimizerHint |
| protected String optimizerHint = null; |
| // protected OracleRowNumExpr rowNumExpr = null; |
| protected int limitRows = -1; |
| protected int skipRows = 0; |
| |
| /** |
| * Constructs an oracle command object. |
| * |
| * @see org.apache.empire.db.DBCommand |
| * |
| * @param db the oracle database object this command belongs to |
| */ |
| public DBCommandOracle(boolean autoPrepareStmt) |
| { |
| super(autoPrepareStmt); |
| } |
| |
| public String getOptimizerHint() |
| { |
| return optimizerHint; |
| } |
| |
| public void setOptimizerHint(String optimizerHint) |
| { |
| this.optimizerHint = optimizerHint; |
| } |
| |
| public void setOptimizerIndexHint(DBIndex index) |
| { |
| if (index==null || index.getTable()==null) |
| throw new InvalidArgumentException("index", index); |
| // Set Index Hint |
| String tableAlias = index.getTable().getAlias(); |
| String indexName = index.getName(); |
| String indexHint = "INDEX ("+tableAlias+" "+indexName+")"; |
| if (StringUtils.isNotEmpty(this.optimizerHint) && this.optimizerHint.indexOf(indexHint)<0) |
| this.optimizerHint = this.optimizerHint + " " + indexHint; |
| else |
| this.optimizerHint = indexHint; |
| } |
| |
| /** |
| * @see DBCommand#clear() |
| */ |
| @Override |
| public void clear() |
| { |
| super.clear(); |
| // Clear oracle specific properties |
| clearConnectBy(); |
| optimizerHint = null; |
| } |
| |
| /** |
| * Clears the connectBy Expression. |
| */ |
| public void clearConnectBy() |
| { |
| connectBy = startWith = null; |
| } |
| |
| public void connectByPrior(DBCompareExpr expr) |
| { |
| this.connectBy = expr; |
| } |
| |
| public void startWith(DBCompareExpr expr) |
| { |
| this.startWith = expr; |
| } |
| |
| @Override |
| public DBCommandOracle limitRows(int limitRows) |
| { |
| // set limit |
| this.limitRows = limitRows; |
| return this; |
| } |
| |
| @Override |
| public DBCommandOracle skipRows(int skipRows) |
| { |
| if (skipRows<0) |
| throw new InvalidArgumentException("skipRows", skipRows); |
| // set skip |
| this.skipRows = skipRows; |
| return this; |
| } |
| |
| @Override |
| public void clearLimit() |
| { |
| // remove skip and limit |
| this.limitRows = -1; |
| this.skipRows = 0; |
| } |
| |
| /** |
| * Creates an Oracle specific select statement |
| * that supports special features of the Oracle DBMS |
| * like e.g. CONNECT BY PRIOR |
| * @param buf the SQL statement |
| */ |
| @Override |
| public synchronized void getSelect(StringBuilder buf) |
| { |
| resetParamUsage(); |
| if (select == null) |
| throw new ObjectNotValidException(this); |
| // limit rows |
| boolean usePreparedStatements = isPreparedStatementsEnabled(); |
| if (limitRows>=0) |
| { // add limitRows and skipRows wrapper |
| buf.append("SELECT * FROM ("); |
| if (skipRows>0) |
| buf.append("SELECT row_.*, rownum rownum_ FROM ("); |
| } |
| // Prepares statement |
| buf.append("SELECT "); |
| if (StringUtils.isNotEmpty(optimizerHint)) |
| { // Append an optimizer hint to the select statement e.g. SELECT /*+ RULE */ |
| buf.append("/*+ ").append(optimizerHint).append(" */ "); |
| } |
| if (selectDistinct) |
| buf.append("DISTINCT "); |
| // Add Select Expressions |
| addListExpr(buf, select, CTX_ALL, ", "); |
| // Join |
| addFrom(buf); |
| // Where |
| addWhere(buf); |
| // Connect By |
| if (connectBy != null) |
| { // Add 'Connect By Prior' Expression |
| buf.append("\r\nCONNECT BY PRIOR "); |
| connectBy.addSQL(buf, CTX_DEFAULT | CTX_NOPARENTHESES); |
| // Start With |
| if (startWith != null) |
| { // Add 'Start With' Expression |
| buf.append("\r\nSTART WITH "); |
| startWith.addSQL(buf, CTX_DEFAULT); |
| } |
| } |
| // Grouping |
| addGrouping(buf); |
| // Order |
| if (orderBy != null) |
| { // Having |
| if (connectBy != null) |
| buf.append("\r\nORDER SIBLINGS BY "); |
| else |
| buf.append("\r\nORDER BY "); |
| // Add List of Order By Expressions |
| addListExpr(buf, orderBy, CTX_DEFAULT, ", "); |
| } |
| // limit rows end |
| if (limitRows>=0) |
| { // add limitRows and skipRows constraints |
| buf.append(") row_ WHERE rownum<="); |
| buf.append(usePreparedStatements ? "?" : String.valueOf(skipRows+limitRows)); |
| if (skipRows>0) |
| { // add skip rows |
| buf.append(") WHERE rownum_>"); |
| buf.append(usePreparedStatements ? "?" : String.valueOf(skipRows)); |
| } |
| } |
| completeParamUsage(); |
| } |
| |
| @Override |
| public Object[] getParamValues() |
| { |
| Object[] params = super.getParamValues(); |
| if (limitRows<0 || !isPreparedStatementsEnabled()) |
| return params; |
| // add limit and skip params |
| int newSize = (params!=null ? params.length : 0)+(skipRows>0 ? 2 : 1); |
| Object[] newParams = new Object[newSize]; |
| // copy params |
| for (int i=0; params!=null && i<params.length; i++) |
| newParams[i]=params[i]; |
| // set skip |
| if (skipRows>0) |
| newParams[--newSize]=skipRows; |
| // set limit |
| newParams[--newSize]=skipRows+limitRows; |
| return newParams; |
| } |
| |
| @Override |
| protected void addUpdateForTable(StringBuilder buf, DBRowSet table) |
| { |
| // Optimizer Hint |
| long context = CTX_FULLNAME; |
| if (StringUtils.isNotEmpty(optimizerHint)) |
| { // Append an optimizer hint to the select statement e.g. SELECT /*+ RULE */ |
| buf.append("/*+ ").append(optimizerHint).append(" */ "); |
| // Append alias (if necessary) |
| if (optimizerHint.contains(table.getAlias())) |
| context |= CTX_ALIAS; |
| } |
| // table |
| table.addSQL(buf, context); |
| // Simple Statement |
| context = CTX_NAME | CTX_VALUE; |
| // Set Expressions |
| buf.append("\r\nSET "); |
| addListExpr(buf, set, context, ", "); |
| // Add Where |
| addWhere(buf, context); |
| } |
| |
| @Override |
| protected void addUpdateWithJoins(StringBuilder buf, DBRowSet table) |
| { |
| // Generate Merge expression |
| buf.setLength(0); |
| buf.append("MERGE INTO "); |
| table.addSQL(buf, CTX_FULLNAME|CTX_ALIAS); |
| // join (only one allowed yet) |
| DBColumnJoinExpr updateJoin = null; |
| for (DBJoinExpr jex : joins) |
| { // The join |
| if (!(jex instanceof DBColumnJoinExpr)) |
| continue; |
| if (jex.isJoinOn(table)==false) |
| continue; |
| // found the join |
| updateJoin = (DBColumnJoinExpr)jex; |
| break; |
| } |
| if (updateJoin==null) |
| throw new ObjectNotValidException(this); |
| // using |
| DBMergeCommand merge = createMergeCommand(); |
| List<DBSetExpr> mergeSet = merge.addUsing(buf, table, updateJoin); |
| // Set Expressions |
| buf.append(")\r\nWHEN MATCHED THEN UPDATE "); |
| buf.append("\r\nSET "); |
| addListExpr(buf, mergeSet, CTX_DEFAULT, ", "); |
| } |
| |
| /** |
| * Creates an Oracle specific delete statement. |
| * @return the delete SQL-Command |
| */ |
| |
| @Override |
| protected void addDeleteForTable(StringBuilder buf, DBRowSet table) |
| { |
| if (StringUtils.isNotEmpty(optimizerHint)) |
| { // Append an optimizer hint to the select statement e.g. SELECT /*+ RULE */ |
| buf.append("/*+ ").append(optimizerHint).append(" */ "); |
| } |
| super.addDeleteForTable(buf, table); |
| } |
| |
| @Override |
| protected void addDeleteWithJoins(StringBuilder buf, DBRowSet table) |
| { |
| if (StringUtils.isNotEmpty(optimizerHint)) |
| { // Append an optimizer hint to the select statement e.g. SELECT /*+ RULE */ |
| buf.append("/*+ ").append(optimizerHint).append(" */ "); |
| } |
| super.addDeleteWithJoins(buf, table); |
| } |
| |
| } |