/*******************************************************************************
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Oracle - initial API and implementation from Oracle TopLink
* Sun Microsystems
******************************************************************************/
package org.eclipse.persistence.platform.database;
import org.eclipse.persistence.internal.databaseaccess.DatabaseCall;
import org.eclipse.persistence.internal.databaseaccess.FieldTypeDefinition;
import org.eclipse.persistence.internal.expressions.ExpressionSQLPrinter;
import org.eclipse.persistence.internal.expressions.SQLSelectStatement;
import org.eclipse.persistence.internal.sessions.AbstractSession;
import org.eclipse.persistence.internal.helper.DatabaseTable;
import org.eclipse.persistence.internal.helper.Helper;
import org.eclipse.persistence.exceptions.ValidationException;
import org.eclipse.persistence.expressions.ExpressionOperator;
import org.eclipse.persistence.queries.ValueReadQuery;
import java.util.Vector;
import java.io.Writer;
import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.Hashtable;
import java.util.Collection;
import java.util.Iterator;
import org.eclipse.persistence.internal.helper.DatabaseField;
/**
* <p><b>Purpose</b>: Provides Derby DBMS specific behavior.
*
* @since TOPLink Essentials 1.0
*/
public class DerbyPlatform extends DB2Platform {
public static final int MAX_CLOB = 2147483647; //The maximum clob/blob size is 2 gigs in Derby.
public static final int MAX_BLOB = MAX_CLOB;
/** Allow sequence support to be disabled for Derby < 10.6.1. */
protected boolean isSequenceSupported;
protected boolean isConnectionDataInitialized;
/**
* INTERNAL:
* TODO: Need to find out how can byte arrays be inlined in Derby
*/
@Override
protected void appendByteArray(byte[] bytes, Writer writer) throws IOException {
super.appendByteArray(bytes, writer);
}
/**
* INTERNAL:
* This method returns the query to select the timestamp from the server
* for Derby.
*/
@Override
public ValueReadQuery getTimestampQuery() {
if (timestampQuery == null) {
timestampQuery = new ValueReadQuery();
timestampQuery.setSQLString("VALUES CURRENT_TIMESTAMP");
}
return timestampQuery;
}
/**
* INTERNAL:
* Not currently used.
*/
@Override
public Vector getNativeTableInfo(String table, String creator, AbstractSession session) {
throw new RuntimeException("Not supported");
}
/**
* Used for stored procedure defs.
*/
@Override
public String getProcedureEndString() {
return getBatchEndString();
}
/**
* Used for stored procedure defs.
*/
@Override
public String getProcedureBeginString() {
return getBatchBeginString();
}
/**
* This method is used to print the output parameter token when stored
* procedures are called
*/
@Override
public String getInOutputProcedureToken() {
return "INOUT";
}
/**
* This is required in the construction of the stored procedures with
* output parameters
*/
@Override
public boolean shouldPrintOutputTokenAtStart() {
//TODO: Check with the reviewer where this is used
return false;
}
/**
* INTERNAL:
* Answers whether platform is Derby
*/
@Override
public boolean isDerby() {
return true;
}
@Override
public boolean isDB2() {
//This class inherits from DB2. But it is not DB2
return false;
}
@Override
public String getSelectForUpdateString() {
return " FOR UPDATE WITH RS";
}
/**
* Allow for the platform to ignore exceptions.
*/
@Override
public boolean shouldIgnoreException(SQLException exception) {
// Nothing is ignored.
return false;
}
/**
* INTERNAL:
*/
@Override
protected String getCreateTempTableSqlSuffix() {
return " ON COMMIT DELETE ROWS NOT LOGGED";
}
/**
* INTERNAL:
* Build the identity query for native sequencing.
*/
@Override
public ValueReadQuery buildSelectQueryForIdentity() {
ValueReadQuery selectQuery = new ValueReadQuery();
selectQuery.setSQLString("values IDENTITY_VAL_LOCAL()");
return selectQuery;
}
/**
* INTERNAL:
* Indicates whether temporary table can specify primary keys (some platforms don't allow that).
* Used by writeCreateTempTableSql method.
*/
@Override
protected boolean shouldTempTableSpecifyPrimaryKeys() {
return false;
}
/**
* INTERNAL:
*/
@Override
protected String getCreateTempTableSqlBodyForTable(DatabaseTable table) {
// returning null includes fields of the table in body
// see javadoc of DatabasePlatform#getCreateTempTableSqlBodyForTable(DataBaseTable)
// for details
return null;
}
/**
* INTERNAL:
* May need to override this method if the platform supports temporary tables
* and the generated sql doesn't work.
* Write an sql string for updating the original table from the temporary table.
* Precondition: supportsTempTables() == true.
* Precondition: pkFields and assignFields don't intersect.
* @parameter Writer writer for writing the sql
* @parameter DatabaseTable table is original table for which temp table is created.
* @parameter Collection pkFields - primary key fields for the original table.
* @parameter Collection assignedFields - fields to be assigned a new value.
*/
@Override
public void writeUpdateOriginalFromTempTableSql(Writer writer, DatabaseTable table,
Collection pkFields,
Collection assignedFields) throws IOException
{
writer.write("UPDATE ");
String tableName = table.getQualifiedNameDelimited(this);
writer.write(tableName);
writer.write(" SET ");
String tempTableName = getTempTableForTable(table).getQualifiedNameDelimited(this);
boolean isFirst = true;
Iterator itFields = assignedFields.iterator();
while(itFields.hasNext()) {
if(isFirst) {
isFirst = false;
} else {
writer.write(", ");
}
DatabaseField field = (DatabaseField)itFields.next();
String fieldName = field.getNameDelimited(this);
writer.write(fieldName);
writer.write(" = (SELECT ");
writer.write(fieldName);
writer.write(" FROM ");
writer.write(tempTableName);
writeAutoJoinWhereClause(writer, null, tableName, pkFields, this);
writer.write(")");
}
writer.write(" WHERE EXISTS(SELECT ");
writer.write(((DatabaseField)pkFields.iterator().next()).getNameDelimited(this));
writer.write(" FROM ");
writer.write(tempTableName);
writeAutoJoinWhereClause(writer, null, tableName, pkFields, this);
writer.write(")");
}
/**
* INTERNAL:
* Append the receiver's field 'identity' constraint clause to a writer.
*/
@Override
public void printFieldIdentityClause(Writer writer) throws ValidationException {
try {
writer.write(" GENERATED BY DEFAULT AS IDENTITY");
} catch (IOException ioException) {
throw ValidationException.fileError(ioException);
}
}
@Override
protected Hashtable buildFieldTypes() {
Hashtable fieldTypeMapping = new Hashtable();
fieldTypeMapping.put(Boolean.class, new FieldTypeDefinition("SMALLINT DEFAULT 0", false));
fieldTypeMapping.put(Integer.class, new FieldTypeDefinition("INTEGER", false));
fieldTypeMapping.put(Long.class, new FieldTypeDefinition("BIGINT", false));
fieldTypeMapping.put(Float.class, new FieldTypeDefinition("FLOAT", false));
fieldTypeMapping.put(Double.class, new FieldTypeDefinition("FLOAT", false));
fieldTypeMapping.put(Short.class, new FieldTypeDefinition("SMALLINT", false));
fieldTypeMapping.put(Byte.class, new FieldTypeDefinition("SMALLINT", false));
fieldTypeMapping.put(java.math.BigInteger.class, new FieldTypeDefinition("BIGINT", false));
fieldTypeMapping.put(java.math.BigDecimal.class, new FieldTypeDefinition("DECIMAL", 15));
fieldTypeMapping.put(Number.class, new FieldTypeDefinition("DECIMAL", 15));
fieldTypeMapping.put(String.class, new FieldTypeDefinition("VARCHAR", DEFAULT_VARCHAR_SIZE));
fieldTypeMapping.put(Character.class, new FieldTypeDefinition("CHAR", 1));
fieldTypeMapping.put(Byte[].class, new FieldTypeDefinition("BLOB", MAX_BLOB));
fieldTypeMapping.put(Character[].class, new FieldTypeDefinition("CLOB", MAX_CLOB));
fieldTypeMapping.put(byte[].class, new FieldTypeDefinition("BLOB", MAX_BLOB));
fieldTypeMapping.put(char[].class, new FieldTypeDefinition("CLOB", MAX_CLOB));
fieldTypeMapping.put(java.sql.Blob.class, new FieldTypeDefinition("BLOB", MAX_BLOB));
fieldTypeMapping.put(java.sql.Clob.class, new FieldTypeDefinition("CLOB", MAX_CLOB));
fieldTypeMapping.put(java.sql.Date.class, new FieldTypeDefinition("DATE", false));
fieldTypeMapping.put(java.sql.Time.class, new FieldTypeDefinition("TIME", false));
fieldTypeMapping.put(java.sql.Timestamp.class, new FieldTypeDefinition("TIMESTAMP", false));
return fieldTypeMapping;
}
@Override
protected void setNullFromDatabaseField(DatabaseField databaseField, PreparedStatement statement, int index) throws SQLException {
int jdbcType = databaseField.getSqlType();
if (jdbcType == DatabaseField.NULL_SQL_TYPE) {
jdbcType = statement.getParameterMetaData().getParameterType(index);
}
statement.setNull(index, jdbcType);
}
/**
* Initialize any platform-specific operators
*/
@Override
protected void initializePlatformOperators() {
super.initializePlatformOperators();
// Derby does not support DECIMAL, but does have a DOUBLE function.
addOperator(ExpressionOperator.simpleFunction(ExpressionOperator.ToNumber, "DOUBLE"));
}
/**
* INTERNAL:
* Use the JDBC maxResults and firstResultIndex setting to compute a value to use when
* limiting the results of a query in SQL. These limits tend to be used in two ways.
*
* 1. MaxRows is the index of the last row to be returned (like JDBC maxResults)
* 2. MaxRows is the number of rows to be returned
*
* Derby uses case #2 and therefore the maxResults has to be altered based on the firstResultIndex.
*/
@Override
public int computeMaxRowsForSQL(int firstResultIndex, int maxResults) {
if (!isSequenceSupported) {
return maxResults;
}
return maxResults - ((firstResultIndex >= 0) ? firstResultIndex : 0);
}
/**
* INTERNAL:
* Derby supports pagination through its "OFFSET n ROWS FETCH NEXT m ROWS" syntax.
*/
@Override
public void printSQLSelectStatement(DatabaseCall call, ExpressionSQLPrinter printer, SQLSelectStatement statement) {
if (!this.isSequenceSupported) {
call.setFields(statement.printSQL(printer));
return;
}
int max = 0;
int firstRow = 0;
if (statement.getQuery()!=null) {
max = statement.getQuery().getMaxRows();
firstRow = statement.getQuery().getFirstResult();
}
if (!(this.shouldUseRownumFiltering()) || (!(max>0) && !(firstRow>0))) {
call.setFields(statement.printSQL(printer));
return;
} else if (max > 0) {
statement.setUseUniqueFieldAliases(true);
call.setFields(statement.printSQL(printer));
printer.printString(" OFFSET ");
printer.printParameter(DatabaseCall.FIRSTRESULT_FIELD);
printer.printString(" ROWS FETCH NEXT ");
printer.printParameter(DatabaseCall.MAXROW_FIELD);
printer.printString(" ROWS ONLY");
} else {
statement.setUseUniqueFieldAliases(true);
call.setFields(statement.printSQL(printer));
printer.printString(" OFFSET ");
printer.printParameter(DatabaseCall.FIRSTRESULT_FIELD);
printer.printString(" ROWS");
}
call.setIgnoreFirstRowSetting(true);
call.setIgnoreMaxResultsSetting(true);
}
/**
* INTERNAL: Derby supports sequence objects as of 10.6.1.
*/
@Override
public boolean supportsSequenceObjects() {
return this.isSequenceSupported;
}
@Override
public boolean isAlterSequenceObjectSupported() {
return false;
}
/**
* INTERNAL: Derby supports sequence objects as of 10.6.1.
*/
@Override
public Writer buildSequenceObjectDeletionWriter(Writer writer, String fullSeqName) throws IOException {
writer.write("DROP SEQUENCE ");
writer.write(fullSeqName);
writer.write(" RESTRICT");
return writer;
}
/**
* INTERNAL:
*/
@Override
public void initializeConnectionData(Connection connection) throws SQLException {
if (this.isConnectionDataInitialized) {
return;
}
String databaseVersion = connection.getMetaData().getDatabaseProductVersion();
if (Helper.compareVersions(databaseVersion, "10.6.1") < 0) {
this.isSequenceSupported = false;
} else {
this.isSequenceSupported = true;
}
this.isConnectionDataInitialized = true;
}
}