Bug 207120 Please model provide an API for data type conversion.
Currently, there're two data types: column data type and parameter data type. But they're inconsistent. Could model provide APIs for conversion between the two types. Thanks. In addition: please check the code into head and 2.2.1 branch, because we have a 2.2.1 bug to fix.
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/util/DataTypeConversionUtil.java
* @param paramType
	 *            the parameter type
	 * @return the column data type
	 */
	public static String converToColumnDataType( String paramType )
	{
		if ( StringUtil.isBlank( paramType ) )
			return null;
		if ( DesignChoiceConstants.PARAM_TYPE_ANY.equals( paramType ) )
			return DesignChoiceConstants.COLUMN_DATA_TYPE_ANY;
		if ( DesignChoiceConstants.PARAM_TYPE_BOOLEAN.equals( paramType ) )
			return DesignChoiceConstants.COLUMN_DATA_TYPE_BOOLEAN;
		if ( DesignChoiceConstants.PARAM_TYPE_DATETIME.equals( paramType ) )
			return DesignChoiceConstants.COLUMN_DATA_TYPE_DATETIME;
		if ( DesignChoiceConstants.PARAM_TYPE_DATE.equals( paramType ) )
			return DesignChoiceConstants.COLUMN_DATA_TYPE_DATE;
		if ( DesignChoiceConstants.PARAM_TYPE_TIME.equals( paramType ) )
			return DesignChoiceConstants.COLUMN_DATA_TYPE_TIME;
		if ( DesignChoiceConstants.PARAM_TYPE_DECIMAL.equals( paramType ) )
			return DesignChoiceConstants.COLUMN_DATA_TYPE_DECIMAL;
		if ( DesignChoiceConstants.PARAM_TYPE_FLOAT.equals( paramType ) )
			return DesignChoiceConstants.COLUMN_DATA_TYPE_FLOAT;
		if ( DesignChoiceConstants.PARAM_TYPE_INTEGER.equals( paramType ) )
			return DesignChoiceConstants.COLUMN_DATA_TYPE_INTEGER;
		if ( DesignChoiceConstants.PARAM_TYPE_STRING.equals( paramType ) )
			return DesignChoiceConstants.COLUMN_DATA_TYPE_STRING;
		return paramType;
	}
}