/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
 * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
 */
package org.hibernate.dialect.function;

import java.sql.Types;

Some databases strictly return the type of the of the aggregation value for AVG which is
problematic in the case of averaging integers because the decimals will be dropped.  The usual workaround
is to cast the integer argument as some form of double/decimal.
Author:
Steve Ebersole/**
 * Some databases strictly return the type of the of the aggregation value for <tt>AVG</tt> which is
 * problematic in the case of averaging integers because the decimals will be dropped.  The usual workaround
 * is to cast the integer argument as some form of double/decimal.
 *
 * @author Steve Ebersole
 */
public class AvgWithArgumentCastFunction extends StandardAnsiSqlAggregationFunctions.AvgFunction {
	private final String castType;

	
Constructs a AvgWithArgumentCastFunction
Params:
castType – The type to cast the avg argument to/**
	 * Constructs a AvgWithArgumentCastFunction
	 *
	 * @param castType The type to cast the avg argument to
	 */
	public AvgWithArgumentCastFunction(String castType) {
		this.castType = castType;
	}

	@Override
	protected String renderArgument(String argument, int firstArgumentJdbcType) {
		if ( firstArgumentJdbcType == Types.DOUBLE || firstArgumentJdbcType == Types.FLOAT ) {
			return argument;
		}
		else {
			return "cast(" + argument + " as " + castType + ")";
		}
	}
}