--- /dev/null
+/*\r
+\r
+ Derby - Class org.apache.derby.impl.sql.execute.DeleteCascadeResultSet\r
+\r
+ Licensed to the Apache Software Foundation (ASF) under one or more\r
+ contributor license agreements. See the NOTICE file distributed with\r
+ this work for additional information regarding copyright ownership.\r
+ The ASF licenses this file to you under the Apache License, Version 2.0\r
+ (the "License"); you may not use this file except in compliance with\r
+ the License. You may obtain a copy of the License at\r
+\r
+ http://www.apache.org/licenses/LICENSE-2.0\r
+\r
+ Unless required by applicable law or agreed to in writing, software\r
+ distributed under the License is distributed on an "AS IS" BASIS,\r
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
+ See the License for the specific language governing permissions and\r
+ limitations under the License.\r
+\r
+ */\r
+\r
+package org.apache.derby.impl.sql.execute;\r
+\r
+import org.apache.derby.iapi.services.sanity.SanityManager;\r
+import org.apache.derby.iapi.error.StandardException;\r
+import org.apache.derby.iapi.sql.execute.ConstantAction;\r
+import org.apache.derby.iapi.sql.execute.CursorResultSet;\r
+import org.apache.derby.iapi.sql.execute.RowChanger;\r
+import org.apache.derby.iapi.sql.execute.NoPutResultSet;\r
+import org.apache.derby.iapi.sql.Activation;\r
+import org.apache.derby.iapi.sql.ResultDescription;\r
+import org.apache.derby.iapi.types.DataValueDescriptor;\r
+import org.apache.derby.iapi.sql.ResultSet;\r
+import org.apache.derby.iapi.store.access.ConglomerateController;\r
+import org.apache.derby.iapi.store.access.TransactionController;\r
+import org.apache.derby.iapi.sql.execute.ExecRow;\r
+import org.apache.derby.iapi.sql.execute.TemporaryRowHolder;\r
+\r
+import org.apache.derby.iapi.reference.SQLState;\r
+\r
+import java.util.Vector;\r
+import java.util.Hashtable;\r
+import java.util.Enumeration;\r
+\r
+/**\r
+ * Delete the rows from the specified base table and executes delete/update\r
+ * on dependent tables depending on the referential actions specified.\r
+ * Note:(beetle:5197) Dependent Resultsets of DeleteCascade Resultset can in\r
+ * any one of the multiple resultsets generated for the same table because of\r
+ * multiple foreign key relationship to the same table. At the bind time ,\r
+ * dependents are binded only once per table.\r
+ * We can not depend on mainNodeTable Flag to fire actions on dependents,\r
+ * it should be done based on whether the resultset has dependent resultsets or not.\r
+ *\r
+ */\r
+public class DeleteCascadeResultSet extends DeleteResultSet\r
+{\r
+\r
+\r
+ public ResultSet[] dependentResultSets;\r
+ private int noDependents =0;\r
+ private CursorResultSet parentSource;\r
+ private FKInfo parentFKInfo;\r
+ private long fkIndexConglomNumber;\r
+ private String resultSetId;\r
+ private boolean mainNodeForTable = true;\r
+ private boolean affectedRows = false;\r
+ private int tempRowHolderId; //this result sets temporary row holder id \r
+\r
+ /*\r
+ * class interface\r
+ * @exception StandardException Thrown on error\r
+ */\r
+ public DeleteCascadeResultSet\r
+ (\r
+ NoPutResultSet source,\r
+ Activation activation,\r
+ int constantActionItem,\r
+ ResultSet[] dependentResultSets,\r
+ String resultSetId\r
+ )\r
+ throws StandardException\r
+ {\r
+\r
+ super(source,\r
+ ((constantActionItem == -1) ?activation.getConstantAction() :\r
+ (ConstantAction)activation.getPreparedStatement().getSavedObject(constantActionItem)),\r
+ activation);\r
+\r
+ ConstantAction passedInConstantAction;\r
+ if(constantActionItem == -1)\r
+ passedInConstantAction = activation.getConstantAction(); //root table\r
+ else\r
+ {\r
+ passedInConstantAction = \r
+ (ConstantAction) activation.getPreparedStatement().getSavedObject(constantActionItem);\r
+ resultDescription = constants.resultDescription;\r
+ }\r
+ cascadeDelete = true;\r
+ this.resultSetId = resultSetId;\r
+ \r
+ if(dependentResultSets != null)\r
+ {\r
+ noDependents = dependentResultSets.length;\r
+ this.dependentResultSets = dependentResultSets;\r
+ }\r
+\r
+ }\r
+\r
+\r
+\r
+ /**\r
+ @exception StandardException Standard Derby error policy\r
+ */\r
+ public void open() throws StandardException\r
+ {\r
+\r
+\r
+ try{\r
+ setup();\r
+ if(isMultipleDeletePathsExist())\r
+ {\r
+ setRowHoldersTypeToUniqueStream();\r
+ //collect until there are no more rows to found\r
+ while(collectAffectedRows(false));\r
+ }else\r
+ {\r
+ collectAffectedRows(false);\r
+ }\r
+ if (! affectedRows)\r
+ {\r
+ activation.addWarning(\r
+ StandardException.newWarning(\r
+ SQLState.LANG_NO_ROW_FOUND));\r
+ }\r
+\r
+ runFkChecker(true); //check for only RESTRICT referential action rule violations\r
+ Hashtable mntHashTable = new Hashtable(); //Hash Table to identify mutiple node for same table cases. \r
+ mergeRowHolders(mntHashTable);\r
+ fireBeforeTriggers(mntHashTable);\r
+ deleteDeferredRows();\r
+ runFkChecker(false); //check for all constraint violations\r
+ rowChangerFinish();\r
+ fireAfterTriggers();\r
+ }finally\r
+ {\r
+ cleanUp();\r
+\r
+ //clear the parent result sets hash table\r
+ activation.clearParentResultSets();\r
+ }\r
+\r
+ endTime = getCurrentTimeMillis();\r
+\r
+ }\r
+ \r
+\r
+ /**\r
+ *Gathers the rows that needs to be deleted/updated \r
+ *and creates a temporary resulsets that will be passed\r
+ *as source to its dependent result sets.\r
+ */\r
+ void setup() throws StandardException\r
+ {\r
+\r
+ /* Cache query plan text for source, before it gets blown away */\r
+ if (lcc.getRunTimeStatisticsMode())\r
+ {\r
+ /* savedSource nulled after run time statistics generation */\r
+ savedSource = source;\r
+ }\r
+\r
+ super.setup();\r
+ activation.setParentResultSet(rowHolder, resultSetId);\r
+ Vector sVector = (Vector) activation.getParentResultSet(resultSetId);\r
+ tempRowHolderId = sVector.size() -1;\r
+ for(int i =0 ; i < noDependents; i++)\r
+ {\r
+ if(dependentResultSets[i] instanceof UpdateResultSet)\r
+ {\r
+ ((UpdateResultSet) dependentResultSets[i]).setup();\r
+ }else\r
+ {\r
+ ((DeleteCascadeResultSet) dependentResultSets[i]).setup();\r
+ }\r
+ }\r
+\r
+ }\r
+\r
+\r
+ boolean collectAffectedRows(boolean rowsFound) throws StandardException\r
+ {\r
+ if(super.collectAffectedRows())\r
+ {\r
+ affectedRows = true;\r
+ rowsFound = true;\r
+ }\r
+\r
+ for(int i =0 ; i < noDependents; i++)\r
+ {\r
+ if(dependentResultSets[i] instanceof UpdateResultSet)\r
+ {\r
+ if(((UpdateResultSet)dependentResultSets[i]).collectAffectedRows())\r
+ rowsFound = true;\r
+ }else\r
+ {\r
+ if(((DeleteCascadeResultSet)\r
+ dependentResultSets[i]).collectAffectedRows(rowsFound))\r
+ rowsFound = true;\r
+ }\r
+ }\r
+\r
+ return rowsFound;\r
+ }\r
+\r
+\r
+ void fireBeforeTriggers(Hashtable msht) throws StandardException\r
+ {\r
+ if(!mainNodeForTable) \r
+ {\r
+ /*to handle case where no table node had qualified rows, in which case no node for\r
+ * the table get marked as mainNodeFor table , one way to identify\r
+ * such case is to look at the mutinode hash table and see if the result id exist ,\r
+ *if it does not means none of the table nodes resulsets got marked\r
+ * as main node for table. If that is the case we mark this\r
+ * resultset as mainNodeTable and put entry in the hash table.\r
+ */\r
+ if(!msht.containsKey(resultSetId))\r
+ {\r
+ mainNodeForTable = true;\r
+ msht.put(resultSetId, resultSetId);\r
+ }\r
+ }\r
+ \r
+ //execute the before triggers on the dependents\r
+ //Defect 5743: Before enabling BEFORE triggers, check DB2 behavior.\r
+ for(int i =0 ; i < noDependents; i++)\r
+ {\r
+ if(dependentResultSets[i] instanceof UpdateResultSet)\r
+ {\r
+ ((UpdateResultSet) dependentResultSets[i]).fireBeforeTriggers();\r
+ }\r
+ else{\r
+ ((DeleteCascadeResultSet)dependentResultSets[i]).fireBeforeTriggers(msht);\r
+ }\r
+ }\r
+\r
+ //If there is more than one node for the same table\r
+ //only one node fires the triggers\r
+ if(mainNodeForTable && constants.deferred)\r
+ super.fireBeforeTriggers();\r
+ }\r
+\r
+ void fireAfterTriggers() throws StandardException\r
+ {\r
+ //fire the After Triggers on the dependent tables, if any rows changed\r
+ for(int i=0 ; i<noDependents && affectedRows; i++){\r
+ if(dependentResultSets[i] instanceof UpdateResultSet)\r
+ {\r
+ ((UpdateResultSet) dependentResultSets[i]).fireAfterTriggers();\r
+ }\r
+ else{\r
+\r
+ ((DeleteCascadeResultSet)dependentResultSets[i]).fireAfterTriggers();\r
+ }\r
+ }\r
+\r
+ //If there is more than one node for the same table\r
+ //, we let only one node fire the triggers.\r
+ if(mainNodeForTable && constants.deferred)\r
+ super.fireAfterTriggers();\r
+ }\r
+\r
+ void deleteDeferredRows() throws StandardException\r
+ {\r
+ \r
+ //delete the rows in the dependents tables\r
+ for(int i =0 ; i < noDependents; i++)\r
+ {\r
+ if(dependentResultSets[i] instanceof UpdateResultSet)\r
+ {\r
+ ((UpdateResultSet) dependentResultSets[i]).updateDeferredRows();\r
+ }\r
+ else{\r
+ ((DeleteCascadeResultSet)dependentResultSets[i]).deleteDeferredRows();\r
+ }\r
+ }\r
+\r
+ \r
+ //If there is more than one node for the same table\r
+ //only one node deletes all the rows.\r
+ if(mainNodeForTable)\r
+ super.deleteDeferredRows();\r
+ }\r
+\r
+ \r
+ void runFkChecker(boolean restrictCheckOnly) throws StandardException\r
+ {\r
+\r
+ //run the Foreign key or primary key Checker on the dependent tables\r
+ for(int i =0 ; i < noDependents; i++)\r
+ { \r
+ if(dependentResultSets[i] instanceof UpdateResultSet)\r
+ {\r
+ ((UpdateResultSet) dependentResultSets[i]).runChecker(restrictCheckOnly);\r
+ }\r
+ else{\r
+ ((DeleteCascadeResultSet)dependentResultSets[i]).runFkChecker(restrictCheckOnly);\r
+ }\r
+ }\r
+\r
+ //If there is more than one node for the same table\r
+ //only one node does all foreign key checks.\r
+ if(mainNodeForTable)\r
+ super.runFkChecker(restrictCheckOnly);\r
+ }\r
+\r
+\r
+ public void cleanUp() throws StandardException\r
+ {\r
+\r
+ super.cleanUp();\r
+ for(int i =0 ; i < noDependents; i++)\r
+ {\r
+ if(dependentResultSets[i] instanceof UpdateResultSet)\r
+ {\r
+ ((UpdateResultSet) dependentResultSets[i]).cleanUp();\r
+ }else\r
+ {\r
+ ((DeleteCascadeResultSet) dependentResultSets[i]).cleanUp();\r
+ }\r
+ }\r
+ \r
+ endTime = getCurrentTimeMillis();\r
+ }\r
+\r
+\r
+ private void rowChangerFinish() throws StandardException\r
+ {\r
+\r
+ rc.finish();\r
+ for(int i =0 ; i < noDependents; i++)\r
+ {\r
+ if(dependentResultSets[i] instanceof UpdateResultSet)\r
+ {\r
+ ((UpdateResultSet) dependentResultSets[i]).rowChangerFinish();\r
+ }else\r
+ {\r
+ ((DeleteCascadeResultSet) dependentResultSets[i]).rowChangerFinish();\r
+ }\r
+ }\r
+ }\r
+\r
+\r
+\r
+ //if there is more than one node for the same table, copy the rows\r
+ // into one node , so that we don't fire trigger more than once.\r
+ private void mergeRowHolders(Hashtable msht) throws StandardException\r
+ {\r
+ if(msht.containsKey(resultSetId) || rowCount ==0)\r
+ {\r
+ //there is already another resultset node that is marked as main\r
+ //node for this table or this resultset has no rows qualified.\r
+ //when none of the resultset nodes for the table has any rows then\r
+ //we mark them as one them as main node in fireBeforeTriggers().\r
+ mainNodeForTable = false;\r
+ }else\r
+ {\r
+ mergeResultSets();\r
+ mainNodeForTable = true;\r
+ msht.put(resultSetId, resultSetId);\r
+ }\r
+ \r
+ for(int i =0 ; i < noDependents; i++)\r
+ { \r
+ if(dependentResultSets[i] instanceof UpdateResultSet)\r
+ {\r
+ return; \r
+ }\r
+ else{\r
+ ((DeleteCascadeResultSet)dependentResultSets[i]).mergeRowHolders(msht);\r
+ }\r
+ }\r
+ }\r
+\r
+\r
+\r
+ private void mergeResultSets() throws StandardException\r
+ {\r
+ Vector sVector = (Vector) activation.getParentResultSet(resultSetId);\r
+ int size = sVector.size();\r
+ // if there is more than one source, we need to merge them into onc\r
+ // temporary result set.\r
+ if(size > 1)\r
+ {\r
+ ExecRow row = null;\r
+ int rowHolderId = 0 ;\r
+ //copy all the vallues in the result set to the current resultset row holder\r
+ while(rowHolderId < size)\r
+ {\r
+ if(rowHolderId == tempRowHolderId )\r
+ {\r
+ //skipping the row holder that we are copying the rows into.\r
+ rowHolderId++;\r
+ continue;\r
+ }\r
+ TemporaryRowHolder currentRowHolder = (TemporaryRowHolder)sVector.elementAt(rowHolderId); \r
+ CursorResultSet rs = currentRowHolder.getResultSet();\r
+ rs.open();\r
+ while ((row = rs.getNextRow()) != null)\r
+ {\r
+ rowHolder.insert(row);\r
+ }\r
+ rs.close();\r
+ rowHolderId++;\r
+ }\r
+ \r
+ }\r
+ }\r
+\r
+\r
+ public void finish() throws StandardException {\r
+ super.finish();\r
+ \r
+ //clear the parent result sets hash table\r
+ //This is necessary in case if we hit any error conditions\r
+ activation.clearParentResultSets();\r
+ }\r
+\r
+\r
+ /* check whether we have mutiple path delete scenario, if\r
+ ** find any retun true. Multiple delete paths exist if we find more than\r
+ ** one parent source resultset for a table involved in the delete cascade\r
+ **/\r
+ private boolean isMultipleDeletePathsExist()\r
+ {\r
+ Hashtable parentResultSets = activation.getParentResultSets();\r
+ for (Enumeration e = parentResultSets.keys() ; e.hasMoreElements() ;) \r
+ {\r
+ String rsId = (String) e.nextElement();\r
+ Vector sVector = (Vector) activation.getParentResultSet(rsId);\r
+ int size = sVector.size();\r
+ if(size > 1)\r
+ {\r
+ return true;\r
+ }\r
+ }\r
+ return false;\r
+ }\r
+\r
+ /*\r
+ **Incases where we have multiple paths we could get the same\r
+ **rows to be deleted mutiple time and also in case of cycles\r
+ **there might be new rows getting added to the row holders through\r
+ **multiple iterations. To handle these case we set the temporary row holders\r
+ ** to be 'uniqStream' type.\r
+ **/\r
+ private void setRowHoldersTypeToUniqueStream()\r
+ {\r
+ Hashtable parentResultSets = activation.getParentResultSets();\r
+ for (Enumeration e = parentResultSets.keys() ; e.hasMoreElements() ;) \r
+ {\r
+ String rsId = (String) e.nextElement();\r
+ Vector sVector = (Vector) activation.getParentResultSet(rsId);\r
+ int size = sVector.size();\r
+ int rowHolderId = 0 ;\r
+ while(rowHolderId < size)\r
+ {\r
+ TemporaryRowHolder currentRowHolder = (TemporaryRowHolder)sVector.elementAt(rowHolderId); \r
+ currentRowHolder.setRowHolderTypeToUniqueStream();\r
+ rowHolderId++;\r
+ }\r
+ }\r
+ }\r
+\r
+}\r
+\r
+\r
+\r
+\r
+\r
+\r
+\r
+\r
+\r
+\r
+\r
+\r
projects / Benchmarks_CSolver.git / blobdiff