Hibernate example source code file (TeradataDialect.java)

This example Hibernate source code file (TeradataDialect.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Hibernate tags/keywords

add, boolean, byteint, byteint, clob, jdbc, no_batch, numeric, sql, sqlfunctiontemplate, sqlfunctiontemplate, string, string, teradatadialect, varchar, varchar

The Hibernate TeradataDialect.java source code

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2010, Red Hat Inc. or third-party contributors as
 * indicated by the @author tags or express copyright attribution
 * statements applied by the authors.  All third-party contributions are
 * distributed under license by Red Hat Inc.
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, 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 Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 */
package org.hibernate.dialect;
import java.sql.Types;
import org.hibernate.HibernateException;
import org.hibernate.cfg.Environment;
import org.hibernate.dialect.function.SQLFunctionTemplate;
import org.hibernate.dialect.function.VarArgsSQLFunction;
import org.hibernate.type.StandardBasicTypes;

/**
 * A dialect for the Teradata database created by MCR as part of the
 * dialect certification process.
 *
 * @author Jay Nance
 */
public class TeradataDialect extends Dialect {

	/**
	 * Constructor
	 */
	public TeradataDialect() {
		super();
		//registerColumnType data types
		registerColumnType( Types.NUMERIC, "NUMERIC($p,$s)" );
		registerColumnType( Types.DOUBLE, "DOUBLE PRECISION" );
		registerColumnType( Types.BIGINT, "NUMERIC(18,0)" );
		registerColumnType( Types.BIT, "BYTEINT" );
		registerColumnType( Types.TINYINT, "BYTEINT" );
		registerColumnType( Types.VARBINARY, "VARBYTE($l)" );
		registerColumnType( Types.BINARY, "BYTEINT" );
		registerColumnType( Types.LONGVARCHAR, "LONG VARCHAR" );
		registerColumnType( Types.CHAR, "CHAR(1)" );
		registerColumnType( Types.DECIMAL, "DECIMAL" );
		registerColumnType( Types.INTEGER, "INTEGER" );
		registerColumnType( Types.SMALLINT, "SMALLINT" );
		registerColumnType( Types.FLOAT, "FLOAT" );
		registerColumnType( Types.VARCHAR, "VARCHAR($l)" );
		registerColumnType( Types.DATE, "DATE" );
		registerColumnType( Types.TIME, "TIME" );
		registerColumnType( Types.TIMESTAMP, "TIMESTAMP" );
		registerColumnType( Types.BOOLEAN, "BYTEINT" );  // hibernate seems to ignore this type...
		registerColumnType( Types.BLOB, "BLOB" );
		registerColumnType( Types.CLOB, "CLOB" );

		registerFunction( "year", new SQLFunctionTemplate( StandardBasicTypes.INTEGER, "extract(year from ?1)" ) );
		registerFunction( "length", new SQLFunctionTemplate( StandardBasicTypes.INTEGER, "character_length(?1)" ) );
		registerFunction( "concat", new VarArgsSQLFunction( StandardBasicTypes.STRING, "(", "||", ")" ) );
		registerFunction( "substring", new SQLFunctionTemplate( StandardBasicTypes.STRING, "substring(?1 from ?2 for ?3)" ) );
		registerFunction( "locate", new SQLFunctionTemplate( StandardBasicTypes.STRING, "position(?1 in ?2)" ) );
		registerFunction( "mod", new SQLFunctionTemplate( StandardBasicTypes.STRING, "?1 mod ?2" ) );
		registerFunction( "str", new SQLFunctionTemplate( StandardBasicTypes.STRING, "cast(?1 as varchar(255))" ) );

		// bit_length feels a bit broken to me. We have to cast to char in order to
		// pass when a numeric value is supplied. But of course the answers given will
		// be wildly different for these two datatypes. 1234.5678 will be 9 bytes as
		// a char string but will be 8 or 16 bytes as a true numeric.
		// Jay Nance 2006-09-22
		registerFunction(
				"bit_length", new SQLFunctionTemplate( StandardBasicTypes.INTEGER, "octet_length(cast(?1 as char))*4" )
		);

		// The preference here would be
		//   SQLFunctionTemplate( StandardBasicTypes.TIMESTAMP, "current_timestamp(?1)", false)
		// but this appears not to work.
		// Jay Nance 2006-09-22
		registerFunction( "current_timestamp", new SQLFunctionTemplate( StandardBasicTypes.TIMESTAMP, "current_timestamp" ) );
		registerFunction( "current_time", new SQLFunctionTemplate( StandardBasicTypes.TIMESTAMP, "current_time" ) );
		registerFunction( "current_date", new SQLFunctionTemplate( StandardBasicTypes.TIMESTAMP, "current_date" ) );
		// IBID for current_time and current_date

		registerKeyword( "password" );
		registerKeyword( "type" );
		registerKeyword( "title" );
		registerKeyword( "year" );
		registerKeyword( "month" );
		registerKeyword( "summary" );
		registerKeyword( "alias" );
		registerKeyword( "value" );
		registerKeyword( "first" );
		registerKeyword( "role" );
		registerKeyword( "account" );
		registerKeyword( "class" );

		// Tell hibernate to use getBytes instead of getBinaryStream
		getDefaultProperties().setProperty( Environment.USE_STREAMS_FOR_BINARY, "false" );
		// No batch statements
		getDefaultProperties().setProperty( Environment.STATEMENT_BATCH_SIZE, NO_BATCH );
	}

	/**
	 * Does this dialect support the <tt>FOR UPDATE syntax?
	 *
	 * @return empty string ... Teradata does not support <tt>FOR UPDATE syntax
	 */
	public String getForUpdateString() {
		return "";
	}

	public boolean supportsIdentityColumns() {
		return false;
	}

	public boolean supportsSequences() {
		return false;
	}

	public String getAddColumnString() {
		return "Add Column";
	}

	public boolean supportsTemporaryTables() {
		return true;
	}

	public String getCreateTemporaryTableString() {
		return "create global temporary table";
	}

	public String getCreateTemporaryTablePostfix() {
		return " on commit preserve rows";
	}

	public Boolean performTemporaryTableDDLInIsolation() {
		return Boolean.TRUE;
	}

	public boolean dropTemporaryTableAfterUse() {
		return false;
	}

	/**
	 * Get the name of the database type associated with the given
	 * <tt>java.sql.Types typecode.
	 *
	 * @param code <tt>java.sql.Types typecode
	 * @param length the length or precision of the column
	 * @param precision the precision of the column
	 * @param scale the scale of the column
	 *
	 * @return the database type name
	 *
	 * @throws HibernateException
	 */
	public String getTypeName(int code, int length, int precision, int scale) throws HibernateException {
		/*
		 * We might want a special case for 19,2. This is very common for money types
		 * and here it is converted to 18,1
		 */
		float f = precision > 0 ? ( float ) scale / ( float ) precision : 0;
		int p = ( precision > 18 ? 18 : precision );
		int s = ( precision > 18 ? ( int ) ( 18.0 * f ) : ( scale > 18 ? 18 : scale ) );

		return super.getTypeName( code, length, p, s );
	}

	public boolean supportsCascadeDelete() {
		return false;
	}

	public boolean supportsCircularCascadeDeleteConstraints() {
		return false;
	}

	public boolean areStringComparisonsCaseInsensitive() {
		return true;
	}

	public boolean supportsEmptyInList() {
		return false;
	}

	public String getSelectClauseNullString(int sqlType) {
		String v = "null";

		switch ( sqlType ) {
			case Types.BIT:
			case Types.TINYINT:
			case Types.SMALLINT:
			case Types.INTEGER:
			case Types.BIGINT:
			case Types.FLOAT:
			case Types.REAL:
			case Types.DOUBLE:
			case Types.NUMERIC:
			case Types.DECIMAL:
				v = "cast(null as decimal)";
				break;
			case Types.CHAR:
			case Types.VARCHAR:
			case Types.LONGVARCHAR:
				v = "cast(null as varchar(255))";
				break;
			case Types.DATE:
			case Types.TIME:
			case Types.TIMESTAMP:
				v = "cast(null as timestamp)";
				break;
			case Types.BINARY:
			case Types.VARBINARY:
			case Types.LONGVARBINARY:
			case Types.NULL:
			case Types.OTHER:
			case Types.JAVA_OBJECT:
			case Types.DISTINCT:
			case Types.STRUCT:
			case Types.ARRAY:
			case Types.BLOB:
			case Types.CLOB:
			case Types.REF:
			case Types.DATALINK:
			case Types.BOOLEAN:
				break;
		}
		return v;
	}

	public String getCreateMultisetTableString() {
		return "create multiset table ";
	}

	public boolean supportsLobValueChangePropogation() {
		return false;
	}

	public boolean doesReadCommittedCauseWritersToBlockReaders() {
		return true;
	}

	public boolean doesRepeatableReadCauseReadersToBlockWriters() {
		return true;
	}

	public boolean supportsBindAsCallableArgument() {
		return false;
	}
}